I have a 1995 volvo 940. A few days ago, when I would go to put the car into park, the key wouldn't turn to position 0. I noticed that the shift button (the one on the stick) was slow to pop up. This morning, when I went to put it in park, it wouldn't. Any ideas on what the problem could be?

 

My dog woke me up about 20 minutes ago (2 am) asking to go outside for some strange reason. I followed him out and saw my baby and began thinking. I inspected the shift lever, and looked down inside past the little brushes that cover up the shifter slot. And guess what, there was a penny jammed way down inside. Every time I put it into park, it wouldn't completely go all the way, so the key wouldn't come out. Yesterday, it must have fallen sideways while driving and then it wouldn't do into park at all.
I feel so stupid but relieved.