Primary Fermentation

Sounds reasonable. If the OG was not high and the room was warm, it could be done.

It could be finished, especially if it was at a higher temperature. Also, if your lid wasn't on tight, then you'd never see bubbles in the airlock (a very common problem).

If you have a hydrometer, check the gravity once a day for about 3 days (or longer) and see if it is continuing to drop. If it stays constant, it is done.

I'm having almost the exact same issue. Brewed it Memorial Day around noon, checked it today and there's no activity at all in airlock, but man did it erupt over the last two days. Overflowing airlock with massive amounts of foam. Ferment temp is around 72-73. I checked the gravity today and I'll check it again on Saturday to see if she's still fermenting. If not then I'll rack to secondary and leave it for two weeks. Like most brewers will tell ya, don't rely on the airlock to determine if it's done or not.....gravity is what counts.

I've had this several times before, I usually just go through the motions, put it into the secondary. but so far everytime I've then thrown it out due to infection. but secondarying it will give you enough time to figure out what's going on.