You gotta start from ground zero again. All of it. NOw!
Yeah, you should be going UP when outside foreleg goes forward. Wanna know why? Because when you are circling , say to the left, when the right fore reaches forward the left rear has just pushed off the ground and is going back and the horse is in a brief moment of suspension, right before the front right touches down and the rear left coils under the body , takes the body weight and pushes forward. So, as the outside hind is pushing, it will rise (any leg that bears weight will cause that part of the horse's body to go up more than the unweighted side, (rear leg/hip, frontleg/shoulder) and it will literally "push" you upward.
Now, you can say, why don't I rise on the inside leg pushing? You can, but because on the circle (left, in this instance) the outside of the horse's body is stretched out longer and there will be a more dramatic push and reach with the outside hind. It is more comfortable for the horse and the rider to post on the outside diagonal.
Make any sense?
Knowing that it takes more energy for your horse to lift you with the hind that you are posting off of will tell you something about possible soreness or lameness in your horse if it tries to always shift you onto one diagonal , preferring that over the other. Might be sore in the hip or leg of the rear leg that should be lifting you when you post to the correct diagonal.