DOG OWNERS HELP!!

I just went to feed my dogs, but one of them won't eat. I put a fresh bowl of water down and she drank half of the large bowl, but will hardly touch her food. This is not like her at all. She usually eats pretty fast (we had to get her a slow feeder). Her belly feels hard and full. Other than all that, she is acting completely normal. Running around, jumping up at me, playing with our other dog. She is about 10 months old, if that means anything. I'm trying to find something online, but thought I would ask here in case anyone else has experienced this. As far as I know, she has not gotten into anything she wasn't supposed to.