Vitreous,
I closed my mouth and covered my nose and held my breath purely as a precautionary measure. I cannot say with certainty that it would have harmed me in the least. I just knew I had inundated my airspace with the tinniest shards, slivers and sheets of glass I have ever seen. I also figured if I can see that much tiny glass particles there were probably a lot of micro particles I could not see. My exhaust took care of probably about 90% of it.
I wore my respirator back in and vacuumed and wiped everything down because I figured that would give me the best chance to remove any lingering particles that could be kicked up into the air and breathed in.
I am absolutely overly cautious when it comes to safety. I even keep one respirator outside of my workspace so it doesn't get contaminated in case something like this happens. My other respirator is in a sealed plastic box in my studio. I have done risk assessment in other fields and I have earned a nickname "Gloom-N-Doom" because I always manage to see the extreme of the risk factor and play out the "what if" scenario to it's final, dangerous end.
It is probably not even sane to contrast your reactions or safety precautions to mine.... I tend to think the sky is falling.... of course it probably is
Otter
Should I worry?
). I just read a blog post in which a lampworker talked about having a blow out and covering his mouth and nose immediately. A month or so ago I had a major blowout while trying to blow a little vessel. I was fascinated to see that the glass looked like saran wrap floating around! I did not think to cover my mouth and nose 
And... although I vacuumed the floor after that I didn't wipe up my work area. 
