Are you using a prong collar, or are you correcting him this way with a flat collar.
IF you are using a prong AND you are noticing a change in behavior that seems to be a shut down in his personality, then yes, you probably are giving too strong a correction. Probably. It is hard to say without seeing it.
By ten months of age, treats should be only for learning new tasks. For walking the dog should be under voice rewards. If something is more exciting than you are, you need to be more engaging than you are being if you want for him to stay with you. Don't nag. Repeating commands, and annoying little tugs will teach your dog that ignoring you is ok. If you are going with corrections, Give the dog a command, one time, give him a moment to comply, and then correct, not a silly tug, but an Eh! with a correction, and move on with him. When he is back where he should be and walking nicely, praise, Good WALK, but be careful to temper it so as not to get him to break it out of excitement for doing it right.
What I would do, is a lot more work without the distractions, and then I would take him back out, but only require the HEEL command for sections where the distractions are fewer and farther between. I would build up to the perfect, comfortable walk I want with the dog. Usually, my HEEL command is for the ring, and for walking across streets. At other times, I just won't tolerate being pulled. Loose lead is fine.
Heidi Ho, Odie
Joy-Joy, Bear Cub, Hepsi-Pepsi
Cujo2, Karma Chameleon
Ramona the Pest, Kojak -- who loves you baby?
Tiny Tinnie, Susie's Uzzi, Kaiah -- The Baby Monster.