Mutton partying like lamb

The problem with carousing all day and night at your brother's wedding, drinking more at a single sitting than you have in probably the previous 12 months combined, singing along at the top of your lungs with the reception band, and generally acting as though you're 10-15 years younger than you actually are, is that - although it is totally, incredibly, voraciously fun - your system, being unused to such treatment, goes into shock, thereby rendering your normal immunities completely impotent.

Which is to say: I had a blast at the wedding but now I have a totally gross cold. Stupid human frailty.