sounds like implantation.. I experienced the same thing, except it lasted the first 3 months of pregnancy. if your not experiencing pain, i wouldn't worry.
I'm having similar problem with you. I've been confused of whether or not I'm pregnant. I normally have regular menstrual cycles and it lasts 5-6 days, but last month, my period or light bleed came a week late and it only lasted for 3 days. It came along with cramps, sensitive nipples, headaches, and fatigues. Then came another month and my period is late again. Everytime I test myself for pregnancy is always negative..
How did you find out that you were pregnant? Every home pregnancy test I took was negative. Maybe I was taking it too soon. When is a good time to take it? I am not hurting at all however I don't know if me taking headache medicine could be the wrong thing for me if I really am pregnant.