I was driving with my g/f today and going about 30 I noticed that the engine was sounding different , i look at the digi and see a 1 and bout 5 seconds later i realized that i was in autostick , i went to the side of the road , tried to get out of it and just went to neutral to get back to normal.

I realize that my arm knocked it to the side I guess but why did my car sound like this and how am I supposed to use this I thought it can't mess up or cause any problems !!!!!

how can I prevent this from happening and how do i get out of autostick mode ?