Tired and just want oreos

I am 28 weeks pregnant. I was so energised yesterday and felt great, but today, I'm just so tired and my brain was so foggy. I kept making mistakes on my work. I took a 1 hr nap during my lunch break, woke up, felt great and mentally refreshed, and went back to work. It's been 2 hours since my nap, I am starting to feel tired again and I just want to procrastinate and eat oreos. I have eaten 6 oreos before my lunch, I know it's bad, shame me if you want to. But is there anyone relate? 🙃