Paddled And Confused

This is the 5th time this year that the coach has found a reason to paddle my ass! I can't prove it but I think he enjoys doing it and singles me out on purpose just to he can blister my butt! No matter how well I try to do in practice he still finds something wrong with what I did. The first couple times he did it right in front of the entire gym class over my shorts but these last few sessions he waited until everyone was gone and made me strip naked and bend over the weight bench for the paddle! This last time he did it really hard and had me crying like a baby in seconds....after the tenth lick I was crying and blubbering like a baby and begging him to stop! He told me the next time it's gonna be even worse and then left me there crying my eyes out. I looked down to pulled up my gym shorts and realized I was fully erect! I was confused as to why I would have a hard on after the coach just finished beating my ass but I just quickly got dressed and hoped that the coach didn't notice my condition. As much as I hate how the coach has been treating me I can't stop thinking about it and I end up jerking off and having a huge orgasm after every session with the paddle! I'm so confused.....