I pleasure myself 3 to 5 times a day, and I can't cum when I am receiving oral

I've been masturbating since I was 11 or younger (I'll be 17 in January). About the time that I was 13 or 14 and we moved into our new home, I started masturbating a lot more. It eventually came to the point where I masturbating 3-5 times a day. I personally don't like to think about the fact that I masturbate this often, but it's true and I really can't help it once I feel turned on. I also believe that this isn't usual for anyone. I've concluded myself that it could be that I masturbate to relieve boredom. Just wondering if this can be anti-beneficial to me in any way? I've been sexually active once and received oral 3 times; however, the first time I had sex, I didn't know that I came. I didn't realize that I had finished until I pulled out. I'm not sure why I didn't feel it, but hopefully someone here can help me out. As for the oral, I can't cum when I'm receiving oral. I feel like I'm about to cum the whole time, but I just don't.