Does this fit the definition of "being on a roll"?

I was working a part-time job, guarding a construction site, where new houses were being built. This was on a Sunday morning and I knew this was going to be a long day. My post was in a construction trailer, located on the construction property. Earlier, I had purchased a Sunday newspaper to read at the site. I was pretty comfortable in the trailer. I located a chair that had wheels on it and stretched back to catch up on the news. I was just about to read the comics, when the chair i was sitting in, began to roll slowly back to the other end of the trailer. My first thought that someone was stealing the trailer and i am about to be kidnapped. I recover from the roll, grab my shotgun, jump out of the trailer…...but, no one, no vehicle was in sight. What the heck? The second rumble gave me a better clue…...EARTHQUAKE. Question: did this rolling chair qualify as a “roll”? And, yes I did have to use Johnny On The Spot right then.