Relax your vaginal (hope this forum prints that word otherwise you may get very confused!!) area is just like any other area of soft tissue and can easily be torn, scraped, grazed by a large penis or by extra forceful intercourse or even prolonged intercourse etc all of which can cause some bleeding - the surprise is that it doesn't happen more often.

You are no more likely to have an std than normal except for the increased likelihood as a result of blood to blood/fluid contact.

Every now and then the same thing happens to me. I don't know why it does sometimes and not others. I think its when i've had prolonged sex or not well lubricated. I might be sore for about a day and maybe i'll see a tiny amount of blood but no biggie

Thankyou for your replys.
We went to the doctor anyway and she said that its probably because we hadnt had sex in a while.
Thankyou anyway.