Pregnant or just going off pain

Me and my S/O had sex the second day of my period (hurt like crazy btw) I came and he came at the same time... We did it again on Sunday while I was still on my period but it was going away... It went away Monday... It's now Thursday and am still camping, my stomach is feeling like butterfly's in it.. Yesterday I felt nausea and had and upset stomach just once when I used the restroom... My back hurts a little not bad.. And my feet hurt... But I just brush it off because my job I stay on my feet all day long.. Send baby dust my way and I'm sending it to everyone also