I spotted for 3 days and then had heavy bleeding for 4 days and ha e been spotting pink and light brown for about 5 days and counting. I had unprotected sex about a month ago and ever since I have been getting headaches, nausea, lightheadedness, back pains, and cramps in my stomach. The cramps vary. I had them right below my belly button on the right side, lower abdomen and a little in my ovaries. I'm not sure what's going on help?? I have taken a few pregnancy tests and they came up negative.

You had your period, that means that it is highly unlikely that you're pregnant. Was the fellow clean? I would get a STI screen and talk to your doctor. It could completely be a unrelated sickness.