What Causes Bleeding Without Pain After Intercourse?

My period ended on February 11th, and I lost my virginity on February 13th. It didn t hurt much, and I didn t bleed even though it was my first time. We used a condom, but we found a tear in it, so on February 14th I took the Plan B pill. The on February 19th, I had sex again. It didn t hurt, but when he took off the condom there was a little bit of blood. I assumed that it had been from my hymen. But then I bled until the 25th, as if it were like my normal period, although it was out of schedule. I wasn t too concerned. But today I had sex for the third time, and again, we used a condom and it didn t hurt, but we found blood on the sheets afterwards. It s been about 12 hours, and I m still bleeding, almost the amount of what my period would normally be. I am not experiencing any pain or anything, but I don t find this to be normal. Do you have any clue as to what this could be caused by?