This is the problem I have been dealing with ever since getting Mirena inserted. I sometimes take Tylenol or Advil PM, Simply Sleep or Melatonin. My MIL recently told me about Valerian Root. I haven't tried it yet, but she says it works. The Tylenol, Advil and Simply Sleep will knock me out pretty good for most of the night. On other nights when I havben't taken any sleeping pills and I happen to wake up in the middle of the night and can't go back to sleep that is when I take the Melatonin. Melatonin helps ease me back to sleep, but doesn't make me feel groggy when I do wake up. I have even taken it at 3:30 in the morning before to help me fall back asleep and I am good to go when I get up at 6:30 with the girls.
I feel your pain. Sleep is so important and it is really hard staying at home with kids when you don't get enough of it.