How To Treat Swollen Vagina?

I had sex, on the beach earlier this morning....
the guy I had sex with used a condom...some of the time. but the condom ripped (I think because of the sand) and he cummed inside of me.
Not only am I worried now that I have a great chance of being pregnant (I'm supposed to be expecting my period around this time) but the sand had been rough on us during intercourse and now I am really really swollen and swore down there.
what should I do about the swelling and about the possibility of being pregnant?