Hi, I'm 19 years old and for the last month or so I have been getting really soar nipples, my Stomach has been very uneasy for the past week or so, I have been quite tired and have been getting a slight headache everyday. I had my last period on the 3rd, and I took a pregnancy test on the 19th but it was negative. I'm not sure what it could be:confused:?? Help lol.