Did I lock the door?

I don't think I'd have trouble remembering whether I'd locked this door.

I'm spending the weekend in Ashdod with my parents (as usual). So earlier this afternoon, I packed up my car, got in, punched in my code and started the engine. I drove as far as the garage gate and thought alarmedly,

"WAIT!!! Did I lock the door???"

(This happens VERY OFTEN.)

I don't normally go back to check, but this time I did.

I parked my car, dashed into the building, got in the elevator, checked my door - lo and behold, of course it was locked! Since I was there, I decided to go in and use the bathroom quickly. I dashed back to my car. Got in, punched in my code, started the engine... and then, 

"WAIT!!! Did I lock the door???"