DESPERATE INSIGHT !! (PERIOD)

Hi, My period is expected to start today but i have a slip up during sex on my last expected fertile window. Starting last friday (Jan. 11) I had uterus pain for a hour or so and mild back cramps. Saturday i had more lower back cramping and sunday i only had vagina pains for half an hour and last night i felt a bit more intense uterus pain. My period however has not started. Im also having sore nipples but my breasts feel normal. And Ive been have very wet discharge and the top of the inside of my vagina feels very firm and tight. Could this be my usual period coming or are these signs of pregnancy? I wanted insight before i went and bought a test. Thanks !