You could be describing my 12-year-old when he was 3, 6, etc.!
You've gotten some great input here that I hope is helpful. It's certainly been helpful to me! I would encourage you to address things earlier than later. My husband is old-school and is convinced it's all just something our son, David, will grow out of. True, but at what cost? I have gotten stronger in getting him help in latter years. A day late, but still helpful.
Our son has definitely had kids back away from him, challenges with teachers, and his psyche and self-confidence are delicate at times because he doesn't understand why people don't like him or some of his behavior. He is coming into his own finally, at 12, but it has been a LONG haul and probably always will be.
Our son has had some amazing teachers who have connected well with him through the years, and we've tried to be as supportive and honest with him as we can to help him understand what's going on. Plus, he has developed some strong friendships, with some friends in the last couple of years, that have profoundly warmed his life and how he sees the world.
But he's one of these kids that tends toward ADHD but doesn't fully fit it. (We and his teachers assessed him but he was borderline ADHD.) SPD might be his thing as well, but again, he's not enough to be diagnosed with it. He is like many kids, I suspect, who fall on the periphery of several labels. No one term fully describes him, but they all describe aspects of him. It's enough to be a challenge, but not enough for services. It's maddening!
That being said, loads of love and hugs and talking at bedtime do wonders for him. At bedtime, he loves to have his scalp scratched from front to back or his temples rubbed, or for me to stay with him as he falls asleep. These techniques help him get in the right frame of mind for sleeping. He also does well with classical music at bedtime to lull him to sleep. (He also likes "The River" (WXRV), but sometimes that keeps him up. If there are too many songs he likes, he sings long into the night, which can be counterproductive.)
At 12, he still LIVES for his stuffed animals and still reaches for his satin tags on his clothes for comfort. I used to get a little weirded out about this, but he knows best what helps to soothe him.
Perhaps because he is an only child, his stuffed animals have become larger than life for our family. They are his siblings, his confidants, etc. But, hey, whatever works, run with it! Fortunately, he has a great group of friends, and us, in real life to keep him grounded.
Children like ours are a delight and a challenge. Books like the Out of Sync Child and Your Spirited Child have been helpful through the years. Children like ours are true gifts of empathy and wonder, along with the hard stuff. Be there for him and don't give up. You may find answers that help you earlier than I did. And if so, Brava!
Best of luck and be persistent. Like someone said, don't be afraid to be the squeaky wheel!
Peace and good humor to you! They will carry you through the tough spots.