OK, so heres my question, I hope you can help:

I had unprotected sex on the last day of my period Feb. 16th and Feb 19th. about 8 days later I started bleeding again around Feb 24th, but this time only lightly for 4 days instead of the 7 days heavy for my cycle. I have not been drinking alcohol, yet wake up as if I have a tremendous hangover. And wake up in the early AM feeling very nauseus. Have been craving things I normally wouldnt. I was due for my period today but have not gotten it yet. I took a pg test, but it was negative, but I feel like I am. My neck has been aching for a week or so, and I have broken out all over, I also have pains on either side of my abdomen, and cramping like crazy (which i usually do not have until the 2nd day of my period, but it comes and goes. It feels like AF is here, so I run and check and It never is. I'm abnormally cranky moreso than ever, even when I'm pmsing and want to cry at everything...My breasts are sore, but I cannot tell if the areola is darker because I have gone tanning. All My PMS symptoms usually occur right after my Period and the cramping usually lasts for a day on the second day of my Period, not weeks before. If I go by the date of my last "normal" period I would have gotten it March 11th. If I go by when I started bleeding again a week after it ended I would have gotten it on the 24th, so either way I'm late, and all hpt say negative. Also, I never get yeast infections, and I have had 2 since last month. And I know I'm always sleepy, but now I'm just overly tired and everything is so exhausting. Does this sound like I could be preggers? I know I should go to the doctor, but just wondering if anyone had any insight. Please help~!