Purely Exhausted

It seems like every day I have even less energy than the day before. I've been spending more time sitting on the ouch or sleeping than doing anything else. The crazier part is, no matter how much I rest or how much sleep I get, I still feel purely exhausted. I wouldnt mind this lack of energy normally, but I'm going to have a baby girl in just three weeks and two days. I know I wont have a lot of time for myself or even with my significant other, so I want to have as much energy as possible to be able to spend with him, my family, and my friends. Hopefully this is just a short phase that will pass, so that I can get my wish and enjoy my last few weeks before becoming a full-time mother.