My boss is pregnant and I assist her with 4 teams and 4 rec classes which is 14 hours a week I also teach two acrobatic classes myself and assist a different teacher on a different day. 
My boss is going to be having twins (her due date is May 30th but twins are known to come early) and I’ll be taking over all classes April and May, I’ve been also subbing random days when she has been in too much pain or overwhelmed to come in. 
I’ve been getting bad anxiety which I’ve never had before and am trying to stay calm but my heart races etc. It’s stupid because I have lesson plans either from her or me making it up and the kids really aren’t that difficult I don’t know why I’m feeling this way.

And tips or anything to help would be super appreciated.
(I also can’t just tell her I can’t do it when I would normally be there assisting her and I don’t have anyone that can assist me)