So Penny's been losing a little bit of weight each day for about the last week. In total she's lost about 3% of her weight over the last week, which on its own isn't out of the ordinary, but it's been consistent weight loss instead of fluctuations. Penny is still eating and pooping; in fact, she's back to finishing all of her pellets before the morning is over. She's gotten into the habit of pulling at the fleece bedding until the edge is accessible so that she can chew on the edge, and she's never done that before, but I would think that if she had a dental problem she would be chewing on the bricks I keep under the water bottles to catch drips (bricks seem like they'd be more effective at wearing down teeth, and it's what one of my previous guinea pigs did when she had dental issues, even though the issue was with her molars). I've solved the fleece-chewing problem by safety-pinning the edges of the fleece to the quilted furniture pads underneath so that she can't pull them toward her (the safety pins are also out of her reach). I emailed the vet, and he said I should keep monitoring Penny's weight but that it might not be a bad idea to do more X-rays to see if anything has changed. I'm trying to decide whether I should wait on the X-rays and see how Penny's weight does over the next few days since she only lost 3% over the last week, or whether I should make the appointment sooner rather than later because she never gained weight over the last week.