Well, the general standard is whether or not the behavior is something you can forego voluntarily if you so decide.
If you CAN'T force yourself to walk down a stairwell normally, or if you CAN'T force yourself to get into a vehicle without checking the tires and looking in back then you are nuts.
On the other hand, if these are voluntary behaviors that you can forego if you wish then you're not nuts. BTW, SAYING you can forego them is not the same as actually being able to.
You are merely eccentric.