Are you lunging her any? Working with her on the ground and using voice and clucking sounds to make her move up?
There is no reason that she should know what to do by just getting kicked in the ribs, if you have not done any basic groundwork with her.
What will probably happen if you don't, is that she will explode, or bolt.
Horses have to be worked with to understand going forwards, and that means groundwork.
You can also work with her while leading, using kissing or clucking to get her moving as you do too, and telling her whoa, and making her stop when you do. Using your fingertips, you can teach her to move over at the front end, middle (sidepass) or rear end. This helps to get her ready to yield from the saddle too.
And your aids should always be whisper light, and kicking one from the get go, only will result in a horse that is not responsive to your cues.
Lunging the horse, makes it look to you for cues, and also lets you teach it that you expect movement when you are making her move.
It also could be that she has never been ridden, if you just got her, or that she could be trained, and you don't know the cues. May also have figured out you don't know what you are doing, so she has decided she will just stand there.
How experienced are you, and how old, is this your first horse, and is there anyone around you that can help you?
Listen to this advice.
A horse isn't born knowing what pressure on the ribs means, and what a pull on the mouth means. You need to teach them. You say she's only been backed for a week? Kicking her and expecting her to know what to do, is like hitting a 2 year old child repetitively for not knowing it's 12x tables, or yelling loudly in English at someone that doesn't speak the language. The horse is confused, it doesn't know what do, and by getting louder, it gets more confused and you will eventually sour the horse and probably get yourself thrown off - and it would not be the horse's fault.
Teach voice aids on the lunge. Before you get on and expect the horse to move off from an aid, you need to have them very much established with walk, trot, canter and 'WOAH' on the lunge. They should also lead very well from the ground. This gives the horse two cues that it understands. You add a rider, and the rider should simply sit quietly in the saddle, not interfering at all, and allow someone on the grond to give the horse the cues it already knows, while it gets accustomed to the sensation of weight on its back.
When it accepts this- THEN the rider can start asking for 'go', 'stop' and 'turn' in conjunction with the already established ground and voice cues. This lessens the confusion for the horse - he already understands two of the 3 cues, and it won't take long for him to associate what he already understands, with the rider cues.