Early morning embarrassment

On my way to school this morning (I teach a class Wednesday mornings at 8AM), I was waiting at a stoplight when a young man asked me a question (in French, of course). I heard the word "feu" which means fire or lighter, but it also means stoplight. Since I was standing at a stoplight I thought he asked me something about if I had hit the button for the crosswalk. I said yes, and then quickly realized he had asked me if I had a lighter because then he asked "can I use it?" At that moment the light turned green and I just said, "No, I'm in a rush "(which I was). I quickly made my way to the school and pushed the button for the receptionist to open the gate. I heard the buzzer, opened the gate and shut it behind me so that no students would try to get in (it was too early for them). I then heard the buzzer and knew that the guy at the stoplight was there...he works at the school! Of course he does (sarcasm...). So, not only did I say to him "yes", I have a lighter and then when he asked to borrow it I said "no" and took off, I shut the gate in his face (not knowing he was right behind me!)!! I'm sure I'll see the guy around at some point. He must think I'm either really rude or crazy! How embarrassing.