Because you mentioned that you used a condom (and good for you!) my first guess would be that you didn't use lube - or, if you did, you didn't use enough lube [that is, CONDOM-SAFE lube like KY or Astroglide! no oils or Vaseline!]
Even if the condom says it's lubricated, there's not enough lube on there for the whole sex act. The lube on the condom is usually only just enough to keep the condom from breaking when you put it on. Before putting on the condom, squeeze a couple of drops of lube on the inside, and then before attempting penetration, use as much lube as you need to on the condom-covered penis and around your vaginal area to make sex comfortable.
Of course, if the bleeding continues, or if you did use plenty of lube and are bleeding anyway, make sure to see your doctor about this, okay?
~lemming, Scarleteen Advocate
"Years ago, I was an angry young man/I'd pretend that I was a billboard/Standing tall by the side of the road/I fell in love with the beautiful highway..."-Talking Heads, "(Nothing but) Flowers"
[This message has been edited by lemming (edited 04-05-2002).]