Changing my guinea pigs' bedding from Carefresh to fleece!?

My little girl piggie, Wendy, won't stop sneezing for the past 2 days! I change her bedding every two days and put a fresh handful of Timothy Hay and some pellets for her to eat. But in the past 3 days, I'm getting closer to the end of the bag of hay so the peices of hay are almost like sawdust. I think that she was breathing that in and it caused her to sneeze so much. I try to check her paws and nose for drainage but she wipes it all off of her nose before I can check it, and refuses to let me touch her feet. I've been using newspaper under her bedding for about 4 days now. I don't know if the smell of it could have affected her, but my other guinea pig, Stretchy, hasn't sneezed or anything. But Wendy has been sneezing very often and very loudly also! So I'm thinking about changing from Carefresh bedding to Fleece. What are the advantages and disadvantages of fleece? And how do i clean it?