Hello, I am seventeen years old. I had unprotected sex a month ago. I have been having stomach cramps , naseua, headaches , and body aches. I thought I was starting my period, but it was four days early. I bled consistently for 4 days and stopped the day my period was suppose to arrive. I have taken 2 at home urine tests, but they both are negative. I am still having stomach pains. Should I get a blood test?