Am I pregnant

I had sex 3 weeks ago we used a condom but the condom slipped out the condom was in my vag when we took it out there was nothing there so I didn’t take a plan b. Since it’s been 3 weeks wouldn’t I have symptoms if I was pregnant? My period is supposed to come in 3 days I been cramping for 2 days. Last night I cried over something stupid. I’m really scaring my self to thinking I’m pregnant I took a tissue instead me to see if it’s blood in there because my period sometimes comes early there was a little blood up there when I checked again it was none. Please don’t be harsh I been using condoms I also had sex 4 days ago wit a condom wit the same guy