I Was Suppose To Get Another Depo Injection October 7

I was suppose to get another depo injection october 7 2014 but i refused, so a few days ago me and my boyfriend had unprotected sex and he ejaculated in me. I began to get watery discharge and some light red spotting. We also had sex today and he ejacualted again inside of me. Hours later i used the bathroom and i notice a yellowish stretching piece of discharge in my underwear. Do you think I am pregnany?