help embarrassed to ask anyone

I've been having alot of sex with several different men just trying to find someone

who can make me orgasm. i can only orgasm by myself and its really really annoying. the guys ive had sex with cant last long enough to make me just by penetration or oral. help what do i do?? I feel so bad because they try so hard and nothing happens. It takes me over a half hour by myself. Is there something wrong with me?