Something is sexually wrong with me

I have never had an orgasm. Not through masturbation or sex. When I masturbate, it feels good for about 30 seconds. It starts to feel like the pleasure is getting strong then.. It disappears. Literally. It just disappears. 
During sex, when he touches me its amazing but its like its overwhelming and my body literally cant take it so i stop him. Or, he keeps doing it and again, the feeling completely disappears. Ive tried everything. We even tried toys, its the same thing. Why? I dont have insurance to go to a doctor yet nor do i even feel comfortavle with going to one lol. But does anyone have an idea as to why this is?