Spotted your post first on HHC; not sure if you're reading here or there.
My thoughts based on the details on HHC: if you cannot get to an emergency vet, get her a vet appointment 1st thing in the morning. Tonight, I'd make sure the area is clean (just water) and dry (pat it dry). Put a little regular strength neosporin/polysporin (NOT the extra strength; NOT the pain relieving) over the area. Clean out her living area. Take all the paper bedding out, scrub down her cage and replace the paper with clean fleece. If you don't have fleece tonight, you can use a clean t-shirt, pillow case, etc... temporarily. Then find her some fleece tomorrow (you don't have to go crazy and get fancy liners... remnants from a fabric store in white or a light color work wonderfully. Flannel also works well. The idea is to find a fabric that doesn't come apart into threads (hedgies have been known to get threads wrapped around toes - which cuts off circulation) - fleece, flannel, and corduroy fit the bill quite well. You want to aim for a light color to allow you to see if she 's bleeding and how much. Dark colors hide the extent of the bleeding.
First thing when you get up in the morning, wash the area again with plain water and pat it dry. Do not rub it dry; do not try and get inventive and use a hair dryer or whatever. Put on another coat of neosporin. Then call the vet for an appointment. The reason I'm thinking you want to get to the vet is (1) to assess for and treat any infection and (2) to help figure out what caused it in the first place -- like if she had a splinter or ingrown quill that become infected or whatnot.