You know what?
If you have THAT tight a deadline for sex, but still have questions, you're rushing. And there is never, ever a good reason to rush.
Intercourse actually shouldn't hurt, nor should any sort of sex. Oftentimes, pain from intercourse is due to nervousness and anxiety cauing a lack of arousal, lack of preparedness, health issues. Sometimes, the first time or two with any sort of vaginal penetration, women with partial hymens may have some discomfort. But not great pain.
So, if it hurts very badly, you stop then. You talk, you dos something else, you wait until you're more aroused (or ready, possibly nother time altogether) and thus, the vaginal canal is more flexible.