Alarm going off randomly

[Sam1ch]

I drove about 40 minutes, parked my car and turned it off, then sat in it for a few minutes. I cannot remember what I did exactly but I either opened the door and the alarm just went off or it went off as I was sitting in my car peacefully waiting. This happened a little over a month ago and I am just now remembering this. Will someone please explain this random event?

P.S. This has only happened to me once

[headhunt3r]

My guesses:

1. You accidentally hit the alarm button on the fob.
2. You locked the doors while inside the car with the fob, then proceeded to unlock the door manually from the inside.