30 weeks and I can't sleep ! Help

I'm 30 weeks and having the worst time sleeping I tend to stay up tossing and turning . I tend to fall asleep around four or five in the morning only to wake up two hours later hungey. I try to sleep after and tend to sleep another couple hours . Then I'm wide awake once more. Any suggestions on what helps you? I'm not really into taking any kind if medication . I have been medication free though out my pregency and want to keep it that way.