My gf and i had unprotected sex i ejaculated in her acouple of times then 2 days later she had a brown red discharge and now she has 2 periods a month?

Check pregnancy test: So there is a possibility that she is pregnant and having some abnormal bleeding ( you did not say how long ago we are talking about) so I would recommend that you guys get a pregnancy test. Next, I would be concerned about a sexually transmitted disease. Finally, it is not unusual for young women to have irregular menses occasionally. She should see a doctor if this becomes bothersome.