I definitely agree to change wet bedding ASAP, it can grow off mold and just in general, its probably not very comfortable to be burrowing through wet bedding.
As to what Karl_McKnight said, I also switched off aspen a little over a year ago. I use thick papertowel layers, enough that Jag can still "burrow" between the layers. I switched at the recommendation of my vet who felt that the chance of impaction, albeit very, very, very small was not worth it. One thing I do once in a while though, is shred some papertowels into strips that Jag can burrow in. Also, I have plants that go in sometimes that have a suction cup and then drape on the ground so she can go under there. And having lots of other hides and things trees to provide coverage seem to make Jag feel comfortable and secure enough. I didn't notice anything different about her behavior when I switched her off aspen either.