I really need some advice. So my last regular period was in January, 4th to 7th to be exact. Seven (7) days after my period I have unprotected sex. The following week that started to feel a bit weird as my breast were swollen and tender, my belly bloated, had backaches, headaches, felt nauseous, peeing a lot and not sleeping sound through the night as I would normally do. Thought I might be having PMS and then what appears to be my period came 1 week in advance. It was different though, it was more spotting than its usual consistency, it was lighter in color and it ended less than 48 hours. During this, I wore just panty liners and not normal pads.  But since then, I have been feeling worse. I have backaches more frequent, I am exhausted, my breast are visible bigger, bloated, feeling a weird tugging feeling in my belly (similar to butterflies), I feel constipated, mild cramps and I am nauseous whether day or night. So I did a pregnancy test which would be 3 days after what seemed to be my period but it was negative.  I am so confused as I know that something seems different in how my body is functioning.  I just hope it is nothing to serious because the symptoms are not adding up for me.  Please shed some light on this for me.