I need advice

I been having sore sensitive nipples for a few weeks now I been cramping a little bit to and lately it's like my heart been racing like crazy and I'm so emotional I'm sure if I'm pregnant or not..I haven't been taking my birth control last.month because I can't afford it but over a month ago when me and my boyfriend had sex it was fine then a few weeks later I ended up bleeding right after we had sex and cramping then to....I think maybe it's just pms but I have no clue.