I have a feeling the cat litter was not as harmless as you think...it's hygroscopic & she is terribly dehydrated. I'd put her in a shallow soak* (water only, not deeper than her body height (1/2" or less of water) for at least an hour, maybe 2+...her old skin needs to come loose. I've never tried "Shed Aid" products for snakes & I'm pretty sure they're a waste of money...they do what water does. She needs help, a.s.a.p. -she's miserable like this, and there's NO WAY she can do this herself.
*Best way: in small plastic carrier w/ ventilated top, 1/2" or less of water. You can put a wadded paper towel in one corner too (for traction & to rub against).
If after the soak it seems her shed is coming off fairly easy, do help with damp towel etc. If she needs more time, give her more time, by all means.
Make sure her head gets wet- mist or gently run water over her.
P.S. Underneath is a really cute snake!![]()