I doubt that choking injuries your piggies throat, he's still eating! I think he likes the attention of you hand feeding him! Put him in his cage and put a piece of lettuce or carrot in there, he'll eat on his own!
My guinea pig choked badly on his food a couple nights ago, now won't eat on his own. I have to hand feed him and he loves it, could the choking possibly injured his throat?
Your guinea pig is probably scared to eat since it choked. Handfeed him for a week and then let him eat on his own.