That doesn't necessarily mean anything at all, though it can...for this reason it's not advised that you sleep with your Dragon or anything like that, but accidents do happen. You need to keep an eye out for any black-bearding, lack of appetite, lethargy, etc.
When you say she's "been in brumation", for how long? And how often does she come out of the brumation. I'm asking because you said she went for a walk, and has apparently eaten some food, and when a Dragon is in an actual full brumation they shouldn't be eating any solid food at all. You can wake them up once a week for a warm
bath and to give them a nice, long drink of water, and then let them go back to sleep, but if they're actually in a full brumation they should not eat any solid food at all until they are completely done and out of it, as the food will just sit inside them and rot.