Can i get pregnant if i took the plan b pill and got on the depo shot four days later

Me and my boyfriend had unprotected sex on a Saturday. I took the plan b pill about an hour afterwards and I also started the depo shot that Thursday. I was supposed to have my period Saturday, but I only bled for about and hour and stopped completely. I read that the shot can sometimes stop your period, but it would take a while to kick in and have it begin to stop it. Is there any way possible that I'm pregnant.?