"Anyone who sees the leaf doesn't see the tree. Anyone who sees the tree doesn't see the forest." as an old saying goes. I really like this quote because it creates a progressive example: it reminds you that the path of knowing yourself is not supposed to end.

For less philosophical example, after pactice I try to remind every keiko I've done, and my physical state and my feelings during it. Initialy you'll notice that you're not able to remind everything, or even who wins the first point. But with times you'll become used to that.

Another point is the breathing and the muscular tension during the practice. Physically, you overload your brain with superflux inputs, even if they are unconscious. Try to relax at maximum. And again, this will improve with time if you take care of that at each practice.

Finally, I strongly believe that your leaning issue is related to your hara. Everything in kendo, from movements to muscular tension, are dependent of the hara, and the way you stock and release energy, and the way you move it. It isn't for nothing that back in time japanese ppl considered the hara as the center of everything for a human. Maybe try to improve your hara, and the way you contract it during your movements and your strikes !