Things that turn me into a wimp include –

Mice, rats, birds (especially in confined spaces).

Films that are too violent – I tend to think twice about a 15 certificate these days.

Phoning someone I don’t know. Especially a large institution.

Erratic driving and I’m in the passenger seat.

Tackling strange burglar alarms.

Trying to explain what I really think/feel about something or someone.

Toothache.

Having my hair cut
……
I’m sure there are more, but these were the ones that came to me in the last three minutes.