Hello,
I can't really help with the drink situation I'm afraid, but I was the same when I was pregnant. I woke up such a lot and didn't feel refreshed. I used to wake up at the same times each night - maybe baby was getting herself into a routine, my friend was the same, do you always wake at certain times?
Late in my pregnancy I found out about a natal hypnotherapy cd. It might sound like gobbledygook to some people, but I listened to it every night and not only did it prepare me for the birth and make me much more relaxed about the whole thing, but it also sent me into a very deep sleep and I felt much more refreshed in the morning. I can give you more details if you can't find it on the net and you're interested.
Good luck!