Sexual dysfunction. Don't want to have,

I am having a problem, in keeping up in bed, I ejaculate too early, like within minutes, sometimes ranging from 2mins to 5mins during intercourse, on the first time after a while then when trying second time its either erectile dysfunction or again ejaculation is quicker somewhere between 5 - 7mins. I had a few bad experiences with my erection when I wanted to have sex, but my penis wasn't supporting I have sex average 2twice to 4 times a month, before I used to masturbate almost every day for 10 years. (my masturbation style is rubbing penis with the bed, just in case this information is somewhere connected so mentioned it). I discovered this problem a year ago. but wasn't that concerning, because I wasn't into a relationship, I had many flings, so didn't bother me much, but now it's becoming a problem as I am committed, and I want to reach her sexual need. we had sex 10 times 2 times were a real success with me having sex pills, such as viagra. which I don't want to have,