G.♣.
My 5 1/2 year old had the surgery when he was 10 months old. We have been very fortunate to not notice any complications, though his pediatrician makes sure to "check" him every visit.
I do remember the surgeon mentioning those types of complications and that they can occur. If there is something that needs to be corrected, I would do it as soon as possible. If he's embarrassed now, he will be more so as he gets older.
Talk to his surgeon. If you're not completely confident, get a second opinion. But do it soon. Definitely get answers soon.
FYI - Hypospadias means the pee hole is in the wrong place. It can be further down the shaft and can be potentially very, very messy and extremely embarrassing. If he's had the surgery, the doctor has moved the hole (and rebuilt the urethra).