Do you mean you cum 3 times in one session? and if you do that seems amazing that you can ejaculate so quickly the 2nd and 3rd time. Generally if your not happy with the time it takes for ejaculation it is caused often by what you think about when penetrating, shift your thoughts to some other subject and you should be able to last as long as your erection (15 to 20 mins) on average. Another way of abstaining is to masturbate before hand, make it as pleasurable as possible and as long as possible your partner can be watching/participating, and ejaculate as much semen as you can. Then on entry after a short time, depending on your recovery ability, you will have a longer session before ejaculating.