No DH, I can't leave our 6 year old at home alone

DS2 threw up at aftercare yesterday and the school nurse thought he should stay home today to rest. Apparently there is a stomach bug that has been going around the 1st grade. Because I work from home, I am stuck with all of the early release days, snow days, sick children. We adopted a dog in October - he is about a year old and needs exercise. I also need exercise. I also need to be able to plan my day - even though i am being laid off I still have things I want/need to accomplish in my last weeks of work. DH does not understand that he needs to help out when stuff happens. He thinks he should not have to make any schedule adjustments, and I'm being ridiculous to not just leave DS2 at home alone while I take care of the dog.