One of my most remembered bloopers was when I was waiting in line at the grocery store after work. Suddenly I felt myself going hypo and immediately reached inside the soda cooler that's strategically placed near the checkout, took out a 20 oz bottle of coke, gulped down half of it, put the cap back on and set it back in the cooler. Must have thought I was home at the fridge.
The next day I recalled what I had done and went back and the bottle was still sitting in the cooler, so I took it out and paid for it.
The second really isn't a blooper, but funny nonetheless. 9 years ago I had surgery for a detached retina. In order to hold it against the back of the eye while it healed, a nitrous oxide bubble was place in the eye. This bubble would gradually decrease in size over the next weeks. I had to wear a neon pink plastic wristband that acknowledged the presence of the bubble because there were certain situtions and medications that could cause it to burst. One day I was waiting at the busstop and a young man pointed to the bracelet and said, "drugs or alcohol?" Apparently residents in treatment programs are given such a bracelet when they have a day pass to leave the facility. I looked him straight in the eye and said, "heroin", He replied, "I thought so. I can spot you guys a mile away."