This happens to me. Always has. I'm 40 and haven't ever been much of a drinker, but whenever I sip something from Budweiser to Jack to mixed drinks, I feel this stinging right at the ring of my anus withing legit like 30-45 seconds or so. It's always seemed a totally unbelievable amount of time. And just a sip will trigger it. Even a tiny sip. So weird.
After having also searched far-and-wide and never found any record of the issue from others, I've just chocked it up to either psychological, or some weird allergen sort of thing. Every several years, I'll look around a bit more. Today, I found your post. Hello, my overdue anal burn buddy!
PS I'm totally not trolling, this is totally a thing and my wife thinks I'm nuts, but finally I can share this record of it happening to someone else!