Pregnant after birth control?

I recently came off Depo shot (Mid April is when my last shot wore off). My bf and I have only been using withdrawal until I can get my Mirena placed. My period is non existent. Sometimes I would bleed for an hour every day for a week, other times I bleed for 24 straight hours, then it'll stop. It literally is so wonky. But recently I noticed my boobs look bigger(he confirmed they do too), they hurt, and my body has just felt off. Occasional nausea too. Haven't tested yet, and no Plan B or anything. So what do you think my chances are? Should I even test or am I over thinking things?