How can I tell if my dogs leg is broke?

I was playing with him and I grabbed his belly, then he yelped. He ran over to my aunt and he couldn't stand on it, he was whimpering. He just layed in my aunts arms he was about to fall asleep. We put him down and he did the same thing. Just a little later, we put him down again and he ran for his bone jumped on the couch and is chewing on it right now. (He's a Weiner dog 1 year old)

If he's running on it, then he's probably fine, but if he keeps showing signs of pain, definitely take him to the vet.

First check his feet (if u can get that close) and see if he got something in bis footand if he's limping and won't walk later on and you should take him to a vet cuz that doesn't really sound good.