Hi there, as long as she is still going to the bathroom I dont think she is impacted even thought she had some sand in her digestive track. I'm leaning more towards brumation. A couple questions though how long have you had your dragon? Has she ever gone through brumation that you know of? I ask because you said she is an adult female. Adults especially females usually go into brumation this time of year. This is a rest period for them before the upcoming breeding season. This brumation can be as sever as sleeping all day, not eating, and pretty much not doing anything for weeks or months. It can be as light as acting normal just not eating, sleeping or being lazy for a couple days a week. Some even don't go through brumation. During this time the majority of dragons wont eat and usually find some place to hide and spend most of the day sleeping. Most of my dragons haven't eaten in months some still act normal some have been asleep for months its just what they do. The best thing is to have a scale and keep an eye on her weight to make sure she isn't losing too much weight. Give her a bath once a week make sure she stays hydrated and also help to pass any sand she has in her digestive track.

This is just my 2 cents on the info you have given(specifically the vet info). Sorry for the long post and hope this was some what helpful. Any questions fel free to ask or PM me...