Hi Angel!

Sorry to hear about your loss and that you're feeling so stressed. I know how scary panic/anxiety attacks can be...I had them about 12 years ago when I was going through a very stressful period as well. For some people, it really can feel like you're having a heart attack! I did wind up taking medication for it for a short while and it did help. The doctor also advised me to avoid (or at least cut back a lot) caffeine and other stimulants. I was taking Sudaphed at the time for a sinus problem and it turns out that I react to it like a person who is taking speed.
FWIW, I don't think going back to a high carb diet, even for a few days, will help. It will probably just send your blood sugars on a wild roller coaster ride and might even make things worse instead of better. DO take care of yourself and take it easy. Do activities that you find relaxing and comforting. Allow yourself to grieve for your loss; keeping emotions like that in stresses the body, too.
I hope you're feeling better soon!