B.,
You sound like you are describing my son (who is now almost 7) when he was that age. The preschool he went to said he behaved the exact same way. They didn't request he go elsewhere - thank goodness - but he did all the same things your son is. BUT, we didn't think it was too much of a problem until he started first grade and then all hell broke loose.
In retrospect, we should have had him evaluated right then and there in kindergarten, but we simply didn't know that the symptoms we were looking at were possibly the symptoms of something more than just a normal immature 4 y/o.
When he started 1st grade, everything you described just intensified to such an extreme that the teacher called us only 2 weeks into the school year and he was just being such a terror. He was getting very aggressive, argumentative, wouldn't do his work, and yet still wanted to sit on or next to the teacher at all times. He wanted to be the teachers helper all the time and couldn't understand when he was told to sit down or whatever.
Anyway, we put him in therapy right away. Honestly, we thought it was some sort of anger management for a 5 y/o. And we were at a loss as what to do with him. Believe me, we felt like horrible parents at that point. The therapist helped but she said he should be evaluated for possible ADHD or even possible autism. This totally freaked us out - the autism part. So immediately, I went into research mode and found that these two diagnoses have very very similar characteristics, so it was no wonder the therapist said to get him checked. We attempted to get into Johns Hopkins Kennedy Kreiger (they're one of the best childrens facilities in the country) but their wait list was around 18 months. I was frantic and was concerned he would fail 1st grade while we were waiting. I also contacted Mt Washington Pediatric Hospital (excellent rating as well) in Baltimore and although it took 6 months (6 loooong months) we got in and after the evaluation, they diagnosed him as ADHD. With their help, help from the therapist and our pediatrician, we agreed to try medication. It worked wonders. We've been very very lucky in that there have been no side effects but the meds have truly made a difference. Within 2 weeks, he was moved up into higher math and reading classes in school and the teacher (who worked so hard to make it as easy as possible for him the whole year - she was a saint!) was very thankful that we were to active and pushing to find something that would help our son be the wonderful boy we knew was in there.
OK, I'm not trying to push medication, I just know that we know what Duncan is like off his meds. He isn't happy with himself either since he just can't control all his impulses. Meds works for us and for Duncan. There are alternative therapies out there which I think do have merit, I just think each family has to decide for themselves what is the best route. BUT, you have to get to a doc and talk to them about these symptoms and see what if anything is going on.
It is hard, stressful, and scary going through all this but the earlier you attend to this, the better - but keep in mind. It often takes weeks/months to get appointments with psychiatrists who are the ones who make the diagnoses, so this is not a quick process which makes it harder because each day your getting more and more stressed because the behavior is still so out of control.
I wish you luck and please feel free to contact me if you have any questions or just want to talk. (sorry this is so long!!)
Julie