Had sex now spotting cramping & backk pain

This isn't my first time having sex but Tuesday me & this guy had sex unprotected & I don't know if he came in me he said he pulled out so I believed it but ever since I was swollen down there & cramping & today I've been spottingg very lightly I don't know what's going on I'm not on birth control or anythingg I used to be on depo but stopped after the first shot should I take a pregnancy test or is this normal