I am 16, don't keep track of my periods. I had my last one around christmas. And I shoukd have had another one by now. I had sex and used a condom on the 3rd of January. I had light brownish discarge for two days. I have back pain. Bloading. Feeling like im gonna throw up. Headaches and a watery discarge that feels like I have started my period. Could I be pregnant?