You should tell your parents ,as they will find out anyway.They have ways of noticing messed underwear, if you know what I mean.I would have them take you to the doctor ,just to make sure its not a serious problem.Many boys still need protective underwear at this age ,and its no big deal ,and no matter what ,don't ever feel like a baby for something like this ,and don't let people call you a baby either.Good luck!