What makes a fear a fear?

What makes it a fear or phobia?
Do you have to hyperventilate or faint at the sight/sound etc of the thing you don’t like? Or do you just have to be made uncomfortable by it?
For example, I really don’t like Moustaches. I don’t have a problem with the people who have them, just the hair itself. they send shivers down my spine and I have to look or sometimes turn away, and even cross the road if someone is walking towards me. I don’t run screaming, or pass out at the mere mention of Moustaches, but I have been known to grimace and I even recoiled into my chair once
No shave Novembers are a real challenge…
Is this a fear? or just an intense dislike?
No offence to anyone with a Moustache of course…