I'm so tired

So I'm 29w2d, FTM and this pregnancy is kicking my ass. I am so tired, I feel sick constantly and my bones feel like jello.

I'm taking my prenatals, eating healthy and a lot, drinking at least 9 cups of water a day and I just can't shake this. It's not only physical either, it's mental too. I've never felt so down in all my life.

My question is, when did you guys start taking off work? Did you work up until your due date/baby was here or did you leave before? I'm just so miserable and I feel like a sack of shit when I go in and then have to leave. My spouse and everyone else says "you're growing a human, you need to take time for yourself" but then I just feel like I'm using my pregnancy as an excuse even though that's not at all the case. Just looking for a little advice from those of you who have been through it all already.