So, do you have anxiety? I ask this because this does sound a bit like anxiety playing a role. You are of a young age and heart related events while possible are not the likely reason.
The thing is, autoimmune disorders are diagnosable. I'm sure the have done blood work which often will reveal an autoimmune disorder. Have you considered being treated for anxiety?
Hi there. I may have an answer. I would suggest that you get the paperwork that comes with your medication and check for side effects listed. I say this because I had the exact same things you wrote about. I was sure I was about to have a stroke. I checked and realised that Scalp Tingle is a major side effect of beta blockers. Your med is a beta blocker, so Im pretty sure that thankfully it is behind your problem. It will tend to subside over time and on a low dose, will go away completely.