Are period & pregnancy symptoms similar?

I'm currently 12dpo. Took a cheap .88 cent Pregnancy test and it was negative of course. I'm currently having sore nipples & they itch and I have to keep rubbing them & putting pressure on them. I also have heavy creamy cervical mucus. My temps are elevated above 98. Do you think those are AF on her way. I have a 28 day cycle, but varies if I'm stressed.