Cramping but no blood

Hey ladies, I recently decided to stop my birth control (Depo Vera) & just day before yesterday I got some cramping the same kind of cramping i get before and while im on my period. I went to the bathroom time and time again but as I wiped there was no blood. Me and my boyfriend had sex on the 14th & honestly im tired of buying hpt just to get hit with a negative. So I was wondering is that normal? Also the cramping was for 1 day. I noticed thst when i was pregnant with my son i had cramping for a few days thinking my period was coming but it didnt.