Depo symptoms or pregnancy symptoms?

I don't know if its a "fake period" or what because I'm having pain in my lower left side,nausea, and I'm getting tired of it. I took the shot march 1st and had unprotected sex on the 9th. Just started getting symptoms on the 14th Are these just symptoms of the shot or what? My period is irregular so it doesn't have a regular schedule. Last month it started on valentines day and I haven't had any kind of bleeding so far. I'm getting a test hopefully at the gy when I talk to her about changing this horrible b/c method.