ShakaZulu:I guess if you push hard enough, you could cause your eyeballs to pop out..........blood, unreal.
Guys, it's not torrents of blood I'm talking about here.

As for BTV...well...let's be honest here, that isn't happening to me anytime soon. If I can master the Frenzel technique I'll be happy. If it's a matter of bursting my eardrums or pinching my nose and blowing, I'll pinch my nose and blow.

My guess is that since I've been concentrating on the left ear mainly, it may have over-aggrevated the left sinuses, as suggested.