Pregnant?

So, first off I am on birth control. I change it how I'm supposed to. Anyways, I'm on the generic version of Ortho Evra now, and it kinda sucks at sticking. The edges always come up ay least a little, but the patch does stay on. My last period was 3 weeks ago, and lasted 3 days instead of 5 and was pretty light. After it ended I became cramping. Now I'm getting SO MANY pimples, I'm insanely tired