Answer: The shirt collar should fit comfortably without being too loose. As tight or snug as possible without being uncomfortable. You should be able to fit 1-2 fingers between the collar and your neck when it is buttoned. You should not have a large gap showing between the collar and neck. Heavier men should make sure their necks are not puffing out over the top of the collar.
Ok if he winced it could mean give a slight involuntary grimace or shrinking movement of the body out of or in anticipation of pain or distress, probably too small;