Boyfriends Masterbation habit.

So my boyfriend is like 2 years younger than me hes 18 & I'm 20. We both lost our virginities like a few months before we meet each other. Since he waited to have sex masterbating for him is like a damn hobby. Sometimes 3x a day. Last night I went to see him since we live 25mins from each other. We had sex 2 times went home got ready for bed we have this night routine of where we fall asleep on FaceTime together (i know corny) then I wake up & I hear him masterbating. Idk if I'm taking this personally like sex with me wasn't enough. I'm kind of pissed off. I know it's a habit of his but do you guys think I have a right to feel like this? Or should I just brush it off?