I had my period a week ago. I had unprotected sex 2 days ago, and now I'm spotting. I'm panicking because this has never happened before. I know it's not my regular period because its too light. It was a pinkish discharge mixed with mucus. Then it was dark brown. Now it is light brown mixed with mucus. Do I have a STD? A Bacterial infection? Or am I Pregnant? Somebody please help me figure this out.