Is this normal behavior? (long sorry)

Here's a little background before I get to the actual question. Our puppy seemed to be ok around other dogs but was always a little timid. I figured this was normal especially because all of the dogs we were around were usually bigger than him. When he was around 9 weeks old, he was playing in a field with my mothers black lab, when all of a sudden she started running at him full speed from half way across the field. I don't know if she thought he would move or what but she plowed right into him! He started crying like I has never heard before....I thought for sure that something was broken. I ran over and picked him up and he was still bawling and he kept pulling his paw to his chest...I thought maybe it was broken. I got him home and he started walking on it a little so I called the vet and told them what happened and they said to keep an eye on it and as long as he kept putting weight on it more and more than it should be fine and they would check it out on his scheduled app at the end of that week. We took him at the end of the week and he was still kind of limping so they did some x rays and they showed nothing. Now, a month later he is fine - no signs of limp or anything else. (I'm getting to a question - I swear). On Monday was his first puppy class and he was ok until one of the bigger puppies started chasing him and then he started yelping (the puppy hadn't even touched him) and hid under a chair for the remainder of playtime. Last night we had a friend over who also has a 3 month old puppy and Dozer was at first excited to see him but the minute the dog got excited at all, he ran and hid under the table. This dog was also male and kept trying to hump him and Dozer did nothing about it!! He gets really excited to see other dogs when we are walking but as soon as he gets close to them and they start to sniff him, he lowers his head, his ears go way down and he tucks his tail. I don't understand - he strains so hard to get to them and then when he does, he's terrified and then when they walk away he starts jumping around like he wants to play! Sorry that this was so long but I'm really concerned because I would like him to grow up to be a well socialized dog but right now he won't even sniff other dogs let alone play with them. I also forgot to mention he is now 13 weeks old.

I think the initial incident had a huge impact on your dog and you will have to provide him with tons of possitive "other" dog interaction without getting hurt. It will take time.

I think the first incident may be a culprit but also your doggy is just being submissive. Is he shaking? Submission is not always fear. Most doggies who come into our dog park like that, cowering, etc, usually gain more and more confidence the longer they stay there. This guy just has to figure out how strong and how big he is. Right now I think his perception of himself is warped a bit.

Be careful though-- some dogs roll dogs over on their backs even when they are already submissive... You have to be able to trust the dogs you're with. Jemma and Boo are really good for that. They're aloof and most scardy-doggies who come in end up really comfortable with them after a short time and even initiate play. You need to find doggies like that-- like a greyhound or other calm big doggies.

No, he doesn't shake at all, he just runs away or cowers as close to the ground as possible with his tail tucked an ears down. Usually my mothers black lab is really good with him and lets him sniff her and bite her tail (gently) but this time it was like something came over her. We are going away for the long weekend to my mothers cottage and her dog will there so I guess we'll see how that goes. :rolleyes:

I think as long as he's not shaking, he should be ok. Just let him consider you as his "home base". You don't have to shelter him, just let him cower at your feet if he ends up there, and remove dogs who are very obviously dominating him.

I would agree that the other dog probably scared the bejesus out of him and now he thinks that all dogs are going to hurt him. He probably really wants to play, but when they start getting close, he remembers his fear. I agree that it will take time and hopefully being around your mom's dog again will show him that being around other dogs doesn't mean he'll get hurt. Good Luck!