Weird/Scary day at work

I work the public meaning most days are very weird because some people just have no common sense. different. I worked at a small gas station/grocery store in my hometown. We were always very busy since it was the closest store that carried about anything you would need. On this one day a car with about five guys pulled up at the gas pump, one of the guys that got out of the car I recognized. The guy had went to my high school and had just been arrested about 2 weeks before for armed robery, so of course my stomach is in knots and I am very worreid. One of the guys pumped some gas, while three came in the store, and one walked around outside. I talked as nice as I could to them as they walked in and called the one I knew by name so maybe he would reliaze he knew me. Me and my manager communicated with our eyes and could both see the fear eachother had. There was only one guy working that day and he was our meat guy, so we got him out there just so it was known it wasn't all women. They didn't buy anything just walked around and payed for the gas. We were thinking they were scoping out the place to come back and rob us. So when they left my manager told me if I were to see that car again to hit our panic button and if nothing happend she would take the blame for hitting it. She said "rather safe then sorry". I think the guys noticed we were pretty busy and there were many camera's, we never saw them again thank goodness. That day by far would have to have been the weirdest/scariest day I ever endured at work.