Can you get a few irregular beats the day after a really stressful ride? I've had little bouts for years, but usually months (or even a year) between those few odd beats.

Yesterday it was hot (90), and the guys decided it was a good day to do a bunch of hills - 1,300 ft of them. This was only my fourth ride of the season, so I'm not in shape yet. I don't usually sweat much, nor does my face usually get red, for me that's always an overheating sign. Today I feel a little off, and was putting laundry on the line this morning and my heart started fluttering - skipping, for about 5 mins. Not dizzy, no pain (girls that would scare the living daylights out of me!).

Anybody had that happen? I'm thinking low potassium or sodium.