Your horse is a sweet looking thing!!
Okay, I think you were doing very well for a beginner, I can't remember how old your horse is, I think it is a youngster.
I think you need to adjust your bridle and put her eyeballs in the middle of the blinders. The blinder her left is too high, I couldn't tell about the right.
If she is truly a yearling or slightly older, good work, and keep it up. I think she is doing great for her age. but start taking up contact on the bit and ask her to start moving forward. Start carrying a whip to get both you and her used to it.
If she is a two year old, deffinatly start getting more contact, start using the saddle for the harness and put the reins through the tugs or use your riding saddle and put the reins through the stirrups. Use the whip and your voice to get her moving forward. It is good that she lets the reins bang around and touch her up and down her legs and sides. Start getting the reins under her tail and between her legs so she gets used to that too.
I think you look great for the stage you are at.
STOP BACKING Backing is an advanced move in driving, you never want backing to be an evasive move, Backing uncommanded is very dangerous. Carrying a whip will help if she backs too much or starts to back uncommanded. I rarely practice backing, Pilgrim starts to anticipate the back if I do it to much, Bad Boy.