Not sure what to do?

I'm not sure what to do. My 5 year old has no diagnoses but is really struggling with hyperactivity and succeeding in Kindergarten.

A brief history... He had his last vaccines at 14 mos. after he stopped talking completely. He's slowly begun talking and is nearly caught up now in conversation abilities and vocabulary.

He developed some autistic tendencies at the same time - hand flapping, intolerance of textures, repeating things once he began talking again. He's also been on the go from the start. We joke that he came out of the womb running (which is pretty much true). He also was never interested in coloring or being read to. He skipped straight over that to writing letters with a pencil and reading himself.

Now at 5 he is very advanced intellectually. He's got a near photographic memory and picks up on new things quickly. He is reading at a 2nd or 3rd grade level, counts into the 1000s and is teaching himself addition. He's taught himself most everything else as well, with only a little direction from us if he got stuck.

His hyperness seems much less about focusing and much more about holding still. It's like his body needs to move. I sometimes wonder if it feels like my RLS. He gets more than enough exercise.

Most of the autistic symptoms have lessened or gone. I've noticed since he's been struggling with school that some of them have come back a bit. Stress?

The third facet to all of this is his upbringing. He has brothers and a sister who are all over 13. Until recently, he has spent more time with them than kids his own age. This is good and bad. He learned to stand his ground among the older kids or get walked on. He is very independent. This mindset doesn't work well in Kindergarten.

He is very friendly but greatly lacking in social skills and has a hard time making friends. I used to think that it was because he couldn't keep up with the conversation of the kids his age, but now, after observing him, I think it's more because he talks much faster and at an older age level. I think he's intimidating and a bit odd to the other kids. Plus he just loves everyone. He's the first to introduce himself. He'd be happy if everyone hugged and held hands and got along. This mindset does not go over well in Kindergarten and especially not with the boys his age. The girls don't seem to mind.

So he has all these things going on, but ultimately, I feel if he was calmer and able to be still, many of the other issues would resolve themselves.

Now, I've read quite a bit on diet and that is another issue. He is a seriously picky eater. He likes fruit, hates veggies, will tolerate meat without anything on it (sauces or casseroles). He'd eat PB&Js all day if we let him. So small changes I can do. Suppliments probably as well if he likes them.

Traditional doctors, counselors and even his teacher have suggested ADHD and would have him drugged and be done with it. I won't do that to him. I'll homeschool him if need be, but I'd rather he be in school to develop the social skills and friends.

I'm very overwhelmed and want him to succeed. He's so bright and I'm afraid if he's not treated properly, he'll lose that love of learning and give up.