Anyone else feel sick and run down?

It's like I hit 35 weeks and I feel aweful..idk if it's just a cold..or something coming on but I feel totally run down all time, I have mild headaches that come and go, congestion, hot flashes, sometimes I get the chills, horrible heartburn and loss of appetite due to it too. Sometimes diarrhea on and off. And then sometimes I feel totally fine and full of energy for like a few hours before I feel horrible again. Anyone else like this? Should I be concerned in getting sick or this just the last few weeks of pregnancy is like? 😭😭😭