Officegirl, so sorry to hear about your aunt! You've been really kind to both her and your mother, you have an awful lot on your plate so its no wonder your BP is high especially tonight.
You need to take care of Yourself. That is your absolute number one priority. Your boss should know that, although she may not have known how much you had today when phoning. Take the time off, and go back when you yourself feel better.
If I were you, and I have high BP too, I'd take next week off. Your doctor will surely give you a medical certificate if you need it.
Take care of yourself. You and your family deserve it.
Hugs,