Perhaps you shouldn't use a blowoff tube then...
If CO2 is getting out and you're not concerned about a clog then there isn't really a need for a blowoff, I just like that extra comfort. As far as if you're keeping more beer that all depends on how much beer you lose through your airlock, but...
I wouldn't be overly worried about sterilization but I would clean your airlock out if there is beer in it. Also, I would put on a blowoff tube. I know you said you never needed one but in this scenario it sounds like you do, also it's much easier to attach a blowoff tube then to clean beer...
It didn't stop prematurely, sometimes the bulk ok fermentation can be completed within 2-4 days. However I would let it sit for another week or two so the yeast can clean up.
Welcome to the forum, and have fun brewing.
Hey just thought I would let everyone know that the Draught Horse (right by Temple University, off Broad Street) is having a homebrew contest June 7th, 2011 with the style judged being wheat beers. Some cool prizes and sure to be a good time...
Never knew that thanks, I got the impression from the OP that it was dumped because of a lack of airlock activity so I just thought I would offer my .02
Sorry about your batch, better luck next time!