Yellow discharge and delayed menstrual cycle

I lost my virginity last October 3 with a stranger. We used protection during sex and then i had sex again october 18 and 19 without protection with a different partner. They're both clean. I'm slightly worried about yellow discharge on my panties, i'm expecting menstrual cycle oct 20-24 pero wala parin. It's too early pa naman to get pt. Is this early signs of pregnancy or its just my body is reacting from fresh sexual activity i had?