Haha, I did the same thing one day on my Mini and pressed that same key. It stopped working or it would close by 1mm every time I pressed something. I can't remember what the key I pressed was but it was another test in the DIS for the closing procedure and that closed it. From there I was nervous to open it again not knowing what it would do or if it'd be stuck again but its been fine ever since.

I also tried a test on my nav and it never worked after that so I had to get a new nav computer.