Moonfroggy, I'm so sorry to hear about your bee sting. I can't even imagine being stung in the ear ... OUCH! Did it swell? I'm amazed that you hung in there and didn't lose control of the bike. I commend you for that.
I was stung in June, lost control of the bike and crashed. Last yr. I was stung on the inside of my lip, that really hurt and did it ever swell. I make it a point now to keep my mouth closed on my rides.
Thank goodness you're not allergic to the bee stings, you've had your share recently. In terms of prevention, I have no clue, just don't let it stop you from doing what you enjoy.
Specialized Ruby/Selle Italia Flow
1991 Specialized Sirrus, steel frame
Dahon Eco C7
Surly Long Haul Trucker/Terry Fly RS
Trident TWIG Recumbent