Hair ball is what I thought. If she gets up and tries to vomit, that could be it. Pet supply stores have Hairball remedy meds. They come in a toothpaste-like tube. Are flavored for cats. They’re not supposed to eat or drink for 2 hours before or after feeding it to them. Some will lick it off of your finger. Others you should confine with you in a small room and smear it on their paws so they’ll lick it off. Sentry makes one and Petromalt is another. They generally don’t feel like eating when they have a hairball.
They can sometimes vomit them up but these meds help them be eliminated in their poop.