Confused. Please help

Saturday afternoon i got what I thought was my period. It was slightly heavy but was 6 days early. Sunday it was very light sometimes the color was red sometimes brown. I had sex Sunday night with no blood. All day Monday I did not bleed but had sex that night and bled during intercourse. It stopped right after And I haven't bled since. All day Monday my while uterus up to right above my tummy was cramping (almost like mild contractions. I have a 6 year old but I was only 18 when I got pregnant with her and don't remember any of the signs I had until I was 8 weeks along and throwing up everywhere). Ive also had to pee a lot the past few days and feel nauseous at times, my boobs have been sore and things have smelt stronger. Hasanyone has this happen to them? And do I wait until I was supposed to get my normal period on Friday to test?