Sorry to hear about skin freak outs! I am sure the weather changing every 5 minutes isn't a help. Can you get a facial? Blue Mercury gives decent samples!
Barre class: the only thing I recommend if you don't want to do it barefoot is a pair of grippy socks like from lulu or under armor. Then you won't slide on the wood floor. And water (though they have it there). They have everything else. Wear anything comfortable - yoga pants and a top. I am totally unflexible and not graceful at all but I could still do it - it pretty welcoming and the instructors correct you as the class goes. I think the big difference will be no ab work in the pregnant class (which is good cuz that sucks!). No video required. If I can do it (well, pre-ivf me), anyone can! Same with yoga.
Avoiding sugar until. Get the GD test results. It isn't easy! Chobani, protein bread, gonna have veggie chilli tomorrow. No fun at all