Plants vs Zombies 2 coins

I was playing the new Feastivus the other day and everything froze up. I had to completely shut my computer down just to get out of the game. When I went back into the game the total for my coins had a minus (-) in front of it. So now when I play it subtracts the coins instead of adding them.  And I can't use my coins for anything. I have numerous plants that need to be upgraded but it won't let me use my coins. It takes me to the screen where you buy them, like I don't have any coins at all.