The hollow eyes and the aggressively protruding teeth, which are completely different from the glossy black eyes and the soft closed mouth of the reference, make the rat look very nasty. Is it a wanted effect?
Something obviously wrong with the hands is that rats have 5 fingers, not 3, and the fingers are quite long, thin and pliable: they should flex and adjust from frame to frame and the palm should be smaller.
The pose has another obvious error: the photo reference you are following is of a still, almost seated rat that spreads its rear legs for balance. Rats are neither rabbits nor kangaroos and they walk with their legs close together.
I agree with Euphronius that flipping one frame is completely insufficient. Apart from plain jerkiness in the legs and head, the tail shouldn't travel so far in the time the rat takes to make a step (another effect of basing the walking animation on a still reference: the tail is actually resting on the ground in a random position).