Wow, that is super weird actually.
Reminds me of an incident I had a few months ago. I arrived at work, by bike. I hadn’t taken the bike for a good while, and I biked harder than I should have. Anyway, I sat down by my desk, and I started salivating.
It wasn’t too much at first, I could keep up by swallowing. I immediately attributed it to the biking and wrote it off, and thought it would pass soon.
But it didn’t. It kept getting worse. More saliva, and faster. I was swallowing mouthfuls at this point, and it was uncomfortable. Like I was being forced to drink lots of water, or being waterboarded.
At last I reached my breaking point and I swiftly walked to the bathroom, locked the door, and just stood with my mouth open and tongue hanging, over the sink, and it was just running, like a faucet opened just enough to be running yet not dripping. This is the part that was similar to your experience—I could feel my saliva… glands? excreting the saliva.
Anyway, this went on for about a minute or two, then it stopped, and I went on with my day.
Have never had something like that happen before, and not since.
Dang, must have been really hot for you to start sweating like this after just 5 meters. 🙃