On the pill & my boyfriend cums inside of me.

Most of my friends say I'm absolutely insane for letting my boyfriend cum inside of me. I am on the pill and every time we have sex he goes inside of me, I've had periods afterwards and everything and the pill really works so it's amazing. The ONLY reason I let him do it is because he says how good it feels or whatever and I just feel bad saying no, I really just want to pleasure him. But it's amazing how the pill really works. I've also been on the pill for 4 months now and I'm 18.