HELP! Why am I bleeding 2 weeks before my period is suppose to start?

Victoria
Why am I bleeding 2 weeks before my period is suppose to start? last night I was cramping really bad like I was gonna get my period and then today when I was having sex with my boyfriend I started bleeding really heavy and then a few minutes later it quit and we continued to have sex. We are TTC. Does this mean Im not able to get pregnant? What's wrong with me??