I think i masterbated one too many times....

Is it normal To be addicted to Masterbation.. and can doing it to much mess up the feeling you get from getting head (oral sex)??
My boyfriend eats me out sooo well :) but I can never cum... I think I masterbated to much because he can eat it for hours n hours and I still never cum. I dont want him to think I dont enjoy it and he wants me to...... you know in his mouth but I can't :(