I had a lot of troubles with my sleep too, but in my opinion they are not directly caused
by yoga practices.
Here is a remedie ( from Eckhart Tolle) : when you go to sleep, lie on your back, hands next to the body or on the belly : go with your attention into the body : feel hands, feet, belly and so on. This to prevent you to fall asleep from mental noise, from thoughts.
Let thoughts fade away, dont support them, only feel your inner body. Then go to sleep.
When you wake up in the middle of the night : dont complain : you are awake, just go again with your attention to the inner body : dont listen to the mental noise : the thoughts will go from them selfes ( and these thoughts can be very disturbing). The most important thing at that moment is to feel your inner body, that is what want and support, let thoughts go from themselfes : the mean nothing.