The sun is shining but still feeling down....?

hey guys, dont know why but im having a really really miserable day today, im 37 weeks pregnant, very excited about the big day but im so fed up...i spent all last night tossing and turning and crying, nothing my partener did or said cheered me up, im kinda giving him a hard time as wel at the mo and i dont know why.i feel so drained, i have no motivation, the dog needs walking, washing needs doing etc and im still sat here in my pj's. what is wrong with me, im only 22 and should have loads or energy but i ant.i just want to cry!!!