What does this mean?

Started feeling first trimester like nauseous-ness a couple days ago... Mainly in the morning. I did throw up yesterday after attempting to eat something small and bland. I felt okay afterwards, exactly like I used to in the beginning of my pregnancy. Also, I've lost my appetite, when usually I'm ravenous when it comes to food lol. I just feel "off" I guess. Not stomach bug/food poisoning coz it's not all the time/haven't changed diet/haven't eaten anything weird or different. 
​Is this coz I'm 39 weeks and near the end? So many BH, very regular but not always consistent, lots of cramps/period like feelings down low, and lots of pressure in my pelvis. Baby is 2/5 engaged. If I go for a walk it sets of very regular strong contractions, but they eventually subside after laying down... 
Any insights welcome :-) xx