Could I be Pregnant? I really need legit answers!?

I had unprotected sex about five days ago. I am on birth control and I have been for a while. Its the ortho evra, (patch) if that matters. I do wear it correctly so I am not worried about my birth control being defective. He didnt ... inside me. I am now having a metallic taste in my mouth. I've heard this can be cause by pregnancy but since it hasnt been very long im not sure if its even possible for it to be from pregnancy. I know that many other things can cause this taste but i really want to rule out pregnancy. Thanks for your answers!