Did you get stung? They last for about 6 hours (the pain part). I did that a few years ago, pushing a walk behind dethatcher over a nest. I ran across the front yard at a high rate of speed for 150 feet or so, but they did get me initially in 3 or 4 spots. They're actually pretty tolerant until you mess with their abode, and usually you don't realize you are until it's too late. Then they're like "okay, volunteers to get this guy outta here".