Ugh. That sounds horrible. I recognize the one part where "I want to stab someone if I hear chewing noises" and I didn't know that had a word until only recently: Misophonia. It literally makes me want to kill or smack someone if they chew or scrape a tea spoon in a cup. I first thought I was just intolerant and sort of was relieved that it's a real 'thing'.

I hope you find out what's 'wrong' - I'm not gonna yell at ya what it could be, but keep on searching, because if something is 'off' it's worth finding out about it <3