Sleeping at high altitude will often mess with your sleep (first night at say, 8000' ft always bothers mine), and there isn't much to be done, except take aleve or ibuprofen and drink liquids and give yourself time to adjust. Generally, it is not recommended to drink or take central nervous system depressants at high altitudes, at least not til you're adjusted. This is really an issue at altitudes over 14,000', where depressants can be dangerous. If at 14K+, you can trying taking diamox, a prescription drug that will help reduce the headaches and speed up adjustment. I used it recently on a high altitude trip, but only because I was up over 15,000-16,000'. I guess it helped some.
...of course, I have been known to stick a flask of Jagermeister in a snowbank for a little shot before bed: doubt this helps my sleep much, but what the heck