I'm in the bathroom!

The other day i was in a bathroom in Subway. It only had one bathroom. So i go in there and decide to not lock the door because i thought there aren't a lot of people in this Subway, everyone saw me go to the bathroom. What are the chances of someone coming in here?! So i do my business and then when i am washing my hands, the door opens and a man stares at me and then i stare back at him. He didn't say anything and neither did I. It was like neither one of us knew what to say and at the same time it wasn't a big deal because i wasn't on the toilet. He was probably thinking Thank GOD!