Implantation Bleeding or Birth Control Spotting??

billie!

Had unprotected sex on May 6 after starting combo birth control pills on May 4. I started them the first day of my period so the packaging said it was immediately effective. Ever since May 18 I have been having occasional brown discharge and the past few days I’ve also been cramping. I know spotting is a common side effect of birth control, so I am not sure if I should be concerned or not. Should I test??