Unsure if pregnant.

Lately during certain times of the day I've been feeling a twinge of nausea where I just want to lay down and do nothing. I've been having mood swings and being really emotional. AF is due in two days according to this period tracker. SO and I have been trying to conceive all month. But not actively. I've been bloating and had horrible cramping last week. But never came back. Also have been constipated and usually I never am. I'm a mother of 1 already he's 3 years old next weekend. 

Please help!