Chick, hopefully this will pass really soon. It has to be frightening for you. When I have palpitations I feel it in my throat. I actually skip a beat. But it comes and goes. Could this be happening to you? I know low potassium can affect the heart. I'm sure you will be much better when this is all under control.
I also will break out in sweats. Been doing that lately but never bothered to check my temperature. I can be fine on minute and then damp the next and I'm waaaay past menopause. I know others have that happen too. Maybe this could be going on, too. I know you have a fever because you have been checking it but perhaps something like this could be happening that makes it seem worse.
Don't let what others think about your illness bother you. YOU know you are having these problems and it is not all in your head. That is so irritating. My daughter had unexplained bouts of vomiting several years back and she is thin to begin with....size 3 in the junior department and she is 32 years old! (Didn't get my genes!) Anyway, she went from doctor to doctor trying to figure this out because she just couldn't eat. Some thought she was bulimic and others told her it was all in her head, too. I remember her coming home sobbing...not knowing what to do. I told her she had seen her Internist and a gastro so how about trying the gynecologist. She did and here she was suffering from endometriosis and THAT was causing her problem. So, you will find out what is causing this and your brother will be eating crow.
I do hope you are doing better this afternoon.
Sherrine