Fear is a natural part of the human experience. It helps keep us stay safe and makes both Halloween and amusement parks more fun. Like everyone not a Navy Seal I have my share of (mostly irrational) fears. I work hard to not let them control me and strive to overcome them whenever possible.
Most notably and most impactful to my sense of adventure is a common one, Acrophobia. Although it is described as "an extreme" fear of heights I have tested my limits on this many many times most notably when climbing for geocaches but also when visiting tall buildings like the Willis (Sears) Tower, flying in a plane or when in the mountains. I have a life goal of skydiving to (in my mind) officially and finally overcome this one.
A little less common is trypanophobia or a fear of needles. In a clinical sense this (and perhaps all of these) are just a dislike or aversion to them as I don't freak out in an uncontrollable way (any more). I just really hate them and at least with needles will sometimes react with nausea although this has improved with age. Getting blood drawn when I was young was something I dreaded. When I had my wisdom teeth taken out I remember waking from the anesthesia and instinctively ripping the IV out to the horror of the nurse.
While I feel I am not the only one in the world with this it is a very specific concern. I know that ENTs say you shouldn't put anything in your ear yet I can't help but clean mine daily with Q-Tips (only name brand, no knock offs for me!) The fear comes from the rather perilous situation I find my eardrums in when I have a small item safely placed deep in to it. I am always worried someone will hit my arm or I will back into a door and somehow ram the cotton swab further into my ear and damage it. This likely results from the many ear issues I've had throughout my life. Ear infections have been very common and I've even had tubes as an adult. This further explains why I want to keep them clean and why I never dunk my head under waster when swimming anymore.