As you may have noticed, there are a few obvious things wrong with your set-up, compared to what we as a forum recommend. Not everyone feeds their Uro everyday, and I have even on a very occasional basis left mine for a weekend, but feeding only twice a week does seem extreme. Do you have an pictures of your Uro?
By scraping her stomach, do you mean making kind of a snake like "S" dance? If you do, then this is a sign of aggression, when coupled with the hissing, and open mouth. They also do this to get comfortable, but you can tell the difference.
My immediate guess, as the others have voiced, is that she has become unacclimated to your presence, and when you walked in and sprayed her she took it as an attack. If you think about it from her point of view I am sure you can see how that mistake could be made. 
In general, the use of things like vitamin sprays is suspect, unless you are extremely careful with their usage, though some vitamin and calcium supplement is a very good idea. Just to make sure that their are not additional issues, what are your tank basking temp, high ambient temp, and low ambient temp? How many hides does she have? What type of substrate do you use? Does she have access to a full spectrum light within 12 inches? These things will all help us help you help her. 
Additionally, as Robyn pointed out, when interacting with online forums capital letters signifiy yelling, and since most of us spend a considerable amount of time on the computer it really is physically painful to try to read a post in all caps. Not everyone realizes this, but now you know.
If you are really interested in helping your little uro friend have the best life possible, which is seems you are since she has such a phenomenally large cage, this forum is an excellent resource with many people who have extensive experience.
Welcome to the forum. 
Elizabeth
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1.0 Mali Uro Archimedes (May he rest in peace)
0.0.1 Egyptian Uro Zuberi Mosca Khu (Mosca)
0.0 Fish
0.1 Sulcata Minnie
1.1 Iguanas Flik and Loki
0.1 Newfoundland Jasmine (RIP)
0.1 Feline Winter
Indiana & Wisconsin