Humming and other sounds is really good. I don't know if that means he is a step closer to talking or not. Jabber and mimicking is great but don't forget to follow up with actual words. If he looks at a ball and babbles something say "good job saying ball". Really enunciate the word ball. After enough repetitions he will connect the word with the object. I'm having a hard time understanding where your problem is with your current therapist. Is she an OT or a ST (occupational or speech therapist?)? Either way, both of you are right, you need to push him but you also need to take your time. It's a very hard and wobbly line to walk. I really don't recommend Head Start. It's really not much better than daycare. If you don't like your therapist and she's the only one in your town, you may need to go to the next town over to find one. The therapist you have for your son not only needs to help him learn but she also needs to help you learn the methods and tricks that are best for him--and you need to feel comfortable with her.

The exercises they have given me for my son focus more on making specific sounds rather than specific words. We sing the DaDa song (sing dada to Twinkle Twinkle Little Star) to help him learn to say dada. It's important that he see your mouth while your speaking, and that you speak slowly. They also told me it's important to give EVERYTHING a one word title. For example, if we pick him up we say "Up" every single time so he starts to associate that word with that action. Ball for any kind of ball, bed for naps and bedtime, etc. And every time he says anything like a word we are suppose to get really excited.
I'm not sure if these exercises pertain exactly to what you are asking, but I hope they help and give you some ideas. We are at the very beginning of our journey and just learning this myself. But I'm happy to pass on any tips we get. I agree with TwiceBlessed, it's important to feel comfortable with your therapist. In my opinion, you should feel as comfortable with your child's therapist as you would your pediatrician or teacher or coach or daycare provider. I don't know how Headstart is in your area, but here it's horrible. It's a glorified daycare at best. They don't have any certified educators or therapists, and often they don't get certified daycare providers even to staff the place. However, they do tend to have access to resources that would otherwise be unavailable to you. So it may be worth looking into even if you choose not to send him there.

moonmaiden had some great tips. Using the beat and pattern of nursery rhymes for one word is great. It's fun and it catches their attention. Because of that they are more likely to "get" the word. Repetition is a huge factor in helping kids learn new words and really process them. If you say up every time he holds his arms up to or whatever cue he uses then he'll eventually associate the word with the motion. Also, grab a sign language book and start on simple signs. Once he gets the sign for a word down (say the sign for eat--which is the thumb and forefinger on the left hand pinched together touching the side of the mouth) start saying eat when he uses the sign. Once he gets it down that the sign and the word go together, slowly wean out the sign and encourage him to use the word eat. It can seem like a very slow process but it works.
Also, check with your local CDSA (Children's Developmental Services Agency). Not only can they do the evaluations, but they can help you find a good therapist that you trust and are comfortable with. They can also help you with funding if you need it (say you don't have private insurance or Medicaid). They are a wonderful resource to use that not many people know about.

well byron said car last night at the park , so thats now, all done, i'm ok, car, mommy, daddy and nana. plus i think he's trying to say the dogs name, should be fun hearing what loki sounds like.

I have four boys and they all took different paths when it comes to talking. I have 3 yo twin boys & one can hold a whole conversation with you, the other sometimes will only answer with one word. It was the same with my older boys also, my oldest sone talked right away, then next one didn't talk for a long time. If they feel they don't need to talk, they don't. Just keep stimulating him, reapeat what he has said & hopefully it will come.

Just wanted to post my own experience.

When my son was 18 months our pediatrician was concerned because he couldn't speak at least 10 words. She wanted us to see a speech therapist. Our son was obviously not hearing impaired and he could follow directions and responded to us very well. He was just really quiet and most of the time didn't even try to talk. We decided it seemed really early to bring him to a speech therapist and decided to wait until he was at least two. By the time his two year birthday came around he was already starting to try to say more words. Now it's four months after his birthday and he talks up a storm! He'll repeat pretty much anything we say and is very conversational. I've heard from many people that when it happens, it happens fast! Every kid is different and learns to speak at different times. I've read many times and heard from people that if hearing isn't a problem, if he follows directions and can respond to requests from you, and he isn't frustrated trying to speak, then he's probably just not ready.

After having 5 kids, I would say not to worry about it now. Each child is different and talks and walks and everything on their own time frame. I didn't think that my 3rd child would ever talk. The little boy across the street was born the day before him and was talking in sentences before he was 2 - I couldn't understand anything mine was saying. My pediatrician told me to be patient that pretty soon I wouldn't be able to shut him up. Guess what- he was right.

Wow...I wasn't too concerned about my daughter but after reading some of the posts here, now I am. She's 19 months old and only says mama, nigh nigh, nice (for petting cats) and just recently 'peez' for please. At her 18 month checkup the doctor said they only expected 3 words by 18 months and so she was fine. But other peoples' doctors said 10? Like others, she can hear and understand just fine. But now I'm a little concerned...

I have a daughter, just about 18m, and she doesn't say much either. She also knows what things are and follows directions. I was told that they really only work on one thing at a time. My daughter can stack more blocks than they say she should be able to at this point and I believe her social skills, as far as playing with others and playing games, are ahead of her time. So the words just aren't her priority or something. I believe it will come, and you also can't really stick to the standards because every child is different.

my ds is 3 and he is barely being able to put three word sentences together, allot of his words arent clear but he has been doing better compared to when he was 18mo, guess it's all at their own pace.