At times my girlfriend likes me to make love to her rather hard and fast, usually from behind, and about 60% of the time this causes me to ejaculate after a short period of time. I've been reading up on premature ejaculation but that doesn't seem to be the problem as I don't have problems during normal sex. I've tried condoms with numbing lubricant on them, but these are usually way too strong and tend to take all feeling out of my penis all together, making me unhard quickly anytime I pull out of her. I've heard keegal (sp?) exercises work, but is there anything else I can do? Is there some trick that pornstars use for this?