I think I got lucky...so far anyway.
Just put my brew in primary about 11:30 last night,which was about 7 hours ago.Looked just now to see if any airlock activity and didn't see bubbles. Then,on closer inspection saw the reason why not....the middle piece wasn't there. I can be pretty forgetful,but knew I had put it in. It was on the cover to my bucket! It had to have gotten active enough to blow it out of there! I put it back on and now it's bubbling loudly enough to hear.
At this point I always feel like Igor and want to yell, "IT'S ALIVE! IT'S Alive!!"