Can anyone tell me what's going on??

Sorry I don't know what group to put this in. Anyway, my period is three days late and it never has been before since I started this app over a year ago. I've been cramping for four days and the last two days I've been feeling sick in my stomach. Especially today when I went to work at my retail job I've been feeling especially sick and... weird in my stomach. not like cramps, but like everything is twisted in my belly. my panties today had two thin red streaks that were thin as a pin and shorter than my pinky. The only time I remember having unprotected sex was last month on Valentine's day but I was on my period... So what do you guys think is up? Late period symptoms or something else?