Dose baby need to be re-circumcised

My son is four months old and was circumcised when he was about a week old. He recently saw one of his grandmas the first one out of everyone to have a boy. She said he doesn’t look circumcised. I’m not sure how it’s supposed to look. But basically the head of his penis can hide in the skin he has.I’m not sure if that’s normal or not I normally do have to move it to clean it. I don’t know if he needs to be redone or what’s going on or this might just be normal. And I’ve also noticed after he had his circumcision the head of the penis has been purple ever sense. I just assumed it was normal he’s four months old now.