fixed wrong?

my friend had her new kitten fixed and it bleeds every so often. they took him to the vet and they werent worried...i am however. since i got my cat fixed and nothing like that happened. did they do something wrong...i read about flutd a blocked urethra...maybe they messed up doing the operation since he was fine b fore it.

Where is it bleeding from?

I would be getting an opinion from a different vet. You made it sound like he's bleeding from his bladder? this is not normal. They don't go anywhere near there during spaying (on purpose anyway).