Hi, Long time lurker on this forum, was wondering if I could get some advice :)

In short, I'm a 29 year old, relatively healthy, average weight male, who has developed a weird intolerance to alcohol, on weekdays only. I can have 1 glass of wine/beer/spirits on a work night or a sunday, and seemingly without exception, I'll be hungover the following day. This applies even if drunk with a 3 course meal, or at Sunday lunch, with over 18 clear hours until I have to be up for work on Monday. These hangovers tend to last all day, and make me feel rather groggy.

However, on a Friday or a Saturday, I can happily down 2/3rds of a bottle of wine, 3 pints or several spirits and mixers and feel few, if any, effects. If I am hungover, after a good breakfast, I feel fine. I'm trying to work out what the cause of the hangovers is, with little success.

One idea I have is differing sleep patterns and stress levels. On a week night, I typically go to bed at around 11-11.30pm, and get up at 7.30am. If I've had even one drink, the anxiety about the hangover means I wake up a couple of times. On a weekend, I tend to go to bed around 1am and get up around 9-9.30am. The fact that I "know" I'll be okay, and the fact that even if I'm hungover, I don't have to go to work, means I sleep right through. I think this means that any hangover is mitigated. 

Another thought it that the hangover is stress related or mentally induced. One day, I had 2 alcohol free beers, and was still hungover because I was stressing about it. I felt tipsy after drinking the beers, despite checking the labels, and because of this, started to stress about a hangover. To me, this indicates the hangover is mentally induced. What can I do to prevent this? I just want to be able to have a single glass of wine or 1 beer with dinner on a work night and not feel like c**p the next day :( All help appreciated :)