^Agreed. Snakes are pretty durable when it comes to this sort of thing. I was recently in a similar situation with one of my live-eating bp's; a rat started gnawing on her lower jaw, really chomping down and there was no way I could get in there to occupy its teeth with something else. I was panicking, but I knew there was nothing I could do, so I watched her kill it and eat it, and there was no wound. There I was preparing to run her to the vet and deal with some gaping wound (that rat had her pretty good...), but there wasn't even a nick. Like I said, they're pretty durable.

If she will eat another asf, go ahead and give it to her. Then, once she's had a few days to digest, take her out of the cage and have a closer look. If there's any open cut dab some non-pain relief Neosporin on it to avoid infection. But I really don't think you have any cause to worry.