Pregnant?

Hey I'm looking for advice, I'm not sure if this is the place for it but I figured why not try? I'm pretty frightened actually. I'm pregnant, most likely. I don't want children right now and can't raise them, I'm 23 and currently in between jobs and I'm living with my grandparents. My boyfriend just left me two, perhaps three weeks ago and when we had sex we always used protection. I haven't had my previous period and in two days is supposed to be my next period. At this point I'm not sure what I should do and I'm just terrified. My ex and I are still good friends but I don't feel right going to him. He's not a bad guy and I know he'd help but I'm just having a lot of mental barriers right now and of course money is an issue for me because I have none and cannot go to my family. Does anybody have any suggestions or advice for me?