You're a scientist? Cool!
The mood calender/chart/journal is a good idea. Also:
I limit my drinking to one drink. I wish I didn't have to, but the high (or euphoria, release, etc) is just not worth the low after. For me, my mood could even drop later that day/night, and last up to 3 days. If it's a long party, I'll ask a friend to share a beer with me twice (so my drink doesn't get warm or flat).
Hope that helps
*cheers!* (pun intended)