Doctors have seen it all. They won't judge unless they are totally unprofessional.
I mean... they won't judge... as long as you don't have something interesting stuck up your ass like a bowling pin. But in either case, it's more important that you get yourself checked out. If you're overdue for a check up, just mention what happened with candor and honesty.
Just tell them you have been wearing diapers recreationally and suddenly this happened without warning. Doctor will probably correctly surmise that you were just lucky to have been wearing at the time (for all the good it did).
BUT I do strongly encourage you to go get checked out because my uncle had a bad case of diverticulitis. In the end (pun intended), they couldn't reconstruct his bowels and he's on a bag for the rest of his life. Your colon health is too important to pass (pun intended) on.