I agree with LittleMissPink, the last link LittleMissPink has provided especially will explain that your DD is at an appropriate stage for her age.
Your DD is at least practicing so i wouldn't worry about it just yet.
Once your DD develops her fine motor skills a bit more ( using her fingers with better control) you will notice that her elbow and forearm will lift off the table and then her wrist will also start to move giving her better control over where she pushes the pencil, which will change her drawing from scribble to pictures.
If you attempt to hold a pencil in a fist grip and lock your wrist and elbow in one position and try to draw you might get a better idea of what i am trying to explain

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A couple of activities which might help her fine motor are those puzzles with the little pegs used to lift the pieces in and out, and a nail board and rubber bands (hammer tall thin nails into a piece of board in a grid pattern and the child stretches the rubber bands over the nails to make patterns/pictures).
I hope some of my rambling has made sense to you!!