Should I take a test?

Skeet

I'm concerned me and my boyfriend have been having unprotected sex for almost 4 months now and I was supposed to get my birth control shot around 2 months ago, I'm not sure how long the shot stays in my system until its no longer affective. I think I just got off my period but it was a lot of spotting and different coloration. I've been having pregnancy symptoms but it could also be period symptoms.

This is my first period in around 3 months but I'm pretty sure that's from my birth control shot.