This has happened to me a couple times when something irritates me to the point where I lose my littleness.
Today my husband had a job interview and he was a nervous wreck before, during, and after. I had a split shift so I came home to make him feel better, but we ended up arguing over something stupid. The side effect was that I got thrown so far off, I found myself entirely adult and fucking miserable. I put on regular underwear and clothing and was about to go back to work when he reached out to me and we calmed things down.
I'll probably pad up again before going back, but does anyone else ever get torn out of their mindset? I find it very disillusioning and uncomfortable.