It's the weight of the belly pressing on your arteries, causing water to pile up in your feet/ankles. I have it too and last week it got worse too for me (39w1d). The bigger you get tje worse it'll get. Elevate feet, drink lots of water, careful with salt intake, try keep your feet moving as much you can (wriggle your toes/ankles). I also got the tip to try epsom salt in lukewarm bath and some brand of pregnancy tea, but i didn't do that cause i don't have the recommended products here in Belgium, and the swelling went down (not away tho) on it's own. As long the swelling gets less over night or when resting up, there is nothing to worry. They say it'll go away as soon you deliver.
I wish it was a sign of labor my feet are constantly swollen five days over due and no baby yet
I've been experiencing swollen ankles & feet probably for the last month, but it used to be only when I was on them too much throughout the day. Just the last few days I've noticed they haven't gone back down like they normally do :/ But I'm with you on just wanting my body back already! (37+3)