Am I pregnant?

I have the BC implant in my arm & I usually have about a 2 day period. I however had bleeding from November 12-23 followed by spotting that just stopped December 5th. I was supposed to start my next period today but with all the bleeding I had last month, I don't know what to expect. I'm having cramping, nausea, diarrhea, headaches and back pain. I don't have a lot of breast tenderness but they feel tingly and static-like. I took a pregnancy test Saturday and it came back with in between results. Am I pregnant or could this be cysts?