Unsure about symptoms

I'm hoping someone can help with ideas on what kind of specialist I can take my son to. He seems to have some potential Asperger's symptoms and/or some OCD, but all are relatively mild as I describe below. Thanks in advance for any help!

My son is seven years old. He is a good boy, plays well with other kids, and has no learning challenges (he's exactly where he should be for first grade). Based on all these facts, I think it's unlikely that he's got a standard form of autism. That being said, my wife and I have noticed for years that something is "not quite right" with him. I'm hoping someone here might recognize what I'm about to describe so we can get him (and ourselves) the right kind of help.

He flaps or shakes his hands every now and then. He can control it, and he says he does it when he's "excited, with lots of energy". He likes to cross and uncross his fingers, and will generally move his hands and fingers in strange ways. He does have some control over this, but it also appears to happen unconciously too (although if he is made aware of it, he can stop). He is very tall for his age, and gangly, and has terrible coordination. We're not sure if the coordination is related to whatever causes the hand movement, or is just a normal trait. He has some strange habits too: If he sees a dog, he must say "Spunky". He likes to smell any new object briefly. He does both these things in a quiet way, so most people wouldn't even notice it. But since I'm around him, I know that it's very consistent. Every single dog he sees someone walking - he must say "Spunky". Finally, he is normally a very even-tempered kid, but every now and then (about 1-2 times per week) he gets "hung up" on something and will have an absolute fit if it doesn't go the way he wants. The most recent episode was him wanting me to put a check into an envelope (I had paid via credit card). No matter how rationally I tried to explain that a check wasn't neccessary, he just went further and further into a complete meltdown. Asking him after he calmed down, it sounded like he really wanted to put something in the envelope - he couldn't stand that it was empty.

Once he's calm, he almost seems sheepish about the meltdown. Any initial thoughts from the experts here?