Girlfriend goes numb after one g-spot orgasm; help plz

so as i said after one g-spot orgasm she is numb inside and her clit is too sensitive for her to find it pleasurable. this wouldn't be such a problem if she didn't cum in less than five minutes, even when i purposely prevent her from climaxing she still comes in less than ten min. i've brought her to multiple climaxes only a couple times before but this is only during super high energy sex, very vigorous and ONLY if i don't stop or even break momentum with the thrusts.