You'll perk up eventually when you hit your "nesting" stage
Yeahhhhhhhh it's natural.
Enjoy it, take rests. Soon you will very busy with the little one. I'm 33 weeks, I'm mostly exhaustedddd, I don't do much either.
Ive been the same way... Im 32 weeks. I do the cooking and cleaning since my husband has the job and its becoming a bit harder... I get tired wanting naps all the time now but when I do have energy I try to continue getting things done around the house.