Background: I used to raise show rabbits and guinea pigs
I've treated a boar with red feet similar to what I can tell from the picture, and multiple rabbits for feet issues.
I had to google the fleece bedding thing- I can't imagine working well in a guinea pigs' cage. If she hardly moves around because her feet hurt, the urine scald would be bad enough on regular bedding much less a piece of fabric. No matter how much you wash some of the urea will be there! Plus the whole chewing fabric thing...
If this was my sow, what I would do:
Get rid of the fleece bedding. Go get that fluffy paper bedding that comes in the weird colors (get the plain type). This stuff
https://www.amazon.com/dp/B007R6G8JW/?tag=skimlinks_replacement-20
It's really soft but should encourage her to shift her weight around because it's not flat. If you can't find that, see if you can find the really soft aspen curls (not chips). Either way put several inches (like 5 or 6) of it in the cage, nice and deep. You may have to put some sort of barrier on the sides of the cage to keep the bedding in. Remove the urine areas daily or even more often as you can so she's not in contact with them.
Now, go to the pharmacy and get three things: Corn pressure relief pads (band aid Brand corn cushions NOT the corn removers!), small amount of Epsom salts, and Preparation H (or the generic hemorrhoid ointment). I'd recommend the ointment type over the cream as it's a better moisture barrier. Bear with me here.... this may seem weird but it worked on my guy.
Make up a tiny amount of epsom salt solution and get it on her foot...JUST her foot don't let her lick it. You could try wrapping a epsom salt soaked paper towel around her foot followed by a plastic bag (to keep you dry) and then just hold her in your lap for 15-20 minutes while it soaks. Or you could soak a towel in it and have her stand on it for 15-20 minutes but you'll have to watch her so she doesn't lick it.
When done, rinse off the foot/feet/whatever is wet well. Pat (don't rub) the whole foot with a soft cloth until dry. Take the Preparation H and rub it on the foot-it won't take much. She'll probably squeal while you are rubbing it because the foot is tender, just keep apologizing but get a layer on it. You don't want so much there that the bedding sticks to it though. What I did is slather it on and keep holding him (on a towel) while I was watching TV and then I wiped the excess off before re caging him to make sure it soaked in. Break out the carrot and petting!
Do this for a week, twice a day if possible-at least get the Preparation H on twice a day. Then, as long as there are no open wounds, wash the foot well with soap and rinse. Apply a corn pressure relief pad to the entire bottom of the foot. You'll have to cut it to size. If she acts all weird and walks funny without putting that foot down (like a cat that stepped on a sticker), stick one on the other foot too so she's balanced. It will fall off on its own in a few days and by then the foot should be much better.
The epsom salts relieves swelling and helps toughen the skin, the Preparation H also helps toughen the skin. If you think there may be any kind of fungal infection (if her nails are yellow or crusty or theres any kind of weeping/hair loss around the toes), get some Tinactin ointment and do that before the preparation H.
Look up "sore hocks" in rabbits and you'll see some other ideas too-its a similar idea. They used to make something called Pad Kote I had to use on my mini rex rabbits' feet but I haven't seen it around lately in the feed stores. It stains everything blue (including you) but it also toughens up the skin. I used to use it on me LOL. Never had to use it on the guinea pigs because the Preparation H trick worked.
Imagine being a shy 14 year old and buying Preparation H and Tinactin at the store... "I swear its for the animals!".
I hope you get her figured out soon. Her shyness and lack of movement may be because her foot hurts and she's not liking all the fuss over it. Oh, for her "floor" time you may want to make that "bed" time and cover a bed with something and let her run on it-bed is soft
. I built a cardboard pen for mine when I'd let them on the bed so they wouldn't run off the sides LOL. :bunny: