My player is freezing

In Stardew Valley, my player is freezing while the rest of the game continues. Usually I'm fishing with the purple fishing pole, the time continues to count, snow continues to fall, other villagers continue to move about, but my player looks like she's all caught up in her fishing pole and just cannot move (though she blinks)...

I've tried pressing different buttons - I'm on an IBM, single player.

Thanks for any help you can give...