I'm annoyed when people sitting close to me shake their legs, feet, or fidget constantly. I think the reason for this is quite obvious,generally they shake the whole damn row with them, and I have a week inner ear lol. Also it's very distracting
General annoyances either mildly trigger some old subconscious unpleasant memories, or just plain are offensive to our senses. High pitched voices bug me, I suffer through lectures with people who speak at high frequencies. In a way it probably hurts my ears, but manifests as annoyance and not pain. Now that I said it I noticed that most my sources of annoyance come from unpleasant sounds, which makes sense, I do have a very sensitive hearing. Perhaps my nervous system just gets overloaded through that specific path. Who knows

Self sooth....is why we do it. [healdove.com]

Human nature

I don't know why we get annoyed. But, I have my LONG list. I laughed out loud at your "...wanna stab him in the throat with a fork." LOL!

I'll gladly hand you the fork for people who:

Hum
Sing with off timing (my ex was always about . 5 seconds behind the lyrics)
Chewing with mouth open
Drinking beverage while mouth is full of food
Sucking teeth (instead of using a toothpick)
Putting makeup on at the table where people are sharing a meal
Use a toothpick indiscreetly - especially in public
Belch with wild abandon and think it's funny or just perfectly okay with others present
Sniff repeatedly (instead of blowing nose)
Men indiscreetly or absentmindedly adjusting their genitals around others
Spits indiscreetly
Use bare hands to repeatedly wipe runny nose
Pop their gum when others are within earshot - ugh.....
Talk indiscreetly on cell phones in waiting lines or in an elevator

I get it -- I'll be single forever and ever. And that's perfectly okay.

we better keep our distance! I have a weird way of whistling softly to myself when I am alone. I never realized I did it until my helper pointed it out. I remember someone who would get infuriated if she heard someone eat a banana even in the most discrete way. who knows. I have to think of my quirks I am sure I have them. The general cacophany of commercials on TV is one

The best answer I have is that it's incongruent with the "mind set" we want to be in. For example, the fact that I ended my last sentence with a preposition, might irritate people who are in the mindset that we should use proper English here.

Before puberty, I was like a boy..carefree, full of jokes, tolerant, etc.
But in my case, increased female hormones at puberty triggered PMS irritability.

You might have some female trait leanings.
Check your fingers; index fingers longer than ring fingers indicate high levels of prenatal female hormones. My own ring fingers are slightly longer than my index ones, indicating high levels of prenatal male hormones, and that was certainly the case.

Every month, with PMS, it was like I was waking up; I'd dump my (current) boyfriend, reconsider my job options, start working on a better life plan, have zero tolerance for bad behavior, etc.
But after menopause, I returned to a stable, cheerful, male-like existence. Not much bothers me now.