All my BTC has come from mining. I've never exchanged any for fiat in either direction. Probably because of this, I've felt numb to the whole "bubble" thing, and it hasn't even seemed to me as though BTC was volatile - my modest BTC pile just kept growing slowly throughout, as planned. Subjectively - it seemed that the world of fiat was all abuzz and trying to buy/sell BTC, but I just didn't (don't) care about short-term fiat/BTC pairing.
There was and is great excitement in the air. I just don't feel part of it, for better or worse. Accumulating fiat has always bored me for some reason - the actual details of the necessary transactions just never seemed "real enough" or "fun enough" to bother with. Ironically, the BTC abstraction seems vividly real to me, perhaps because it doesn't change on political whims.
As to cause of the "panic", I would guess mischief rather than simple fear/greed patterns, but who knows? It's hard to guess why it would kick in at any particular moment.
Let's talk it all over in 20 years or so. For now, I'm just glad to see that the "panic" seems to have stopped most of the "ain't it awful" buzz about BFL for a while. ;-)
Same here. Only difference is that I have spent plenty of bitcoins on dumb stuff. I still have my fair share, and I feel immune to panic selling because I have little cost involved. Bitcoin makes a great hobby.