Diaper rash or something else?

Kristy

My little man is 2.5 and today has been the first time we've had decent weather this year (60°). Hes been complaining of his penis being painful and itchy. His scrotum is really red and idk if it's just diaper rash from being a little sweaty( I did some aquaphor on it after the bath) or if it could be something else, he sometimes gets diaper rash on his butt but never elsewhere, any thoughts?