Insanely fast Nottingham fermentation?

On Sunday, I decided to brew a pretty simple small batch BIAB AG pale ale, because as we all know a full carboy is a happy carboy. Everything went very well with my brewday, according to Beersmith I hit 77.5% efficiency, I ended up with about 2.75 gallons of wort in the carboy, and I came in at 1.052 OG (expected 1.048). Aerated the wort by rocking/shaking the carboy, then pitched a packet of Nottingham in at a wort temp of about 68. I did not rehydrate the yeast, I just pitched it on top. Closed everything up and set it in the basement (ambient temp of ~65 degrees).

Monday morning before work, I went to check on it and the airlock was furiously bubbling, roughly once every 2 seconds. Had a nice big krausen, I'd say about an inch and a half thick. Smelled glorious. Came home Monday night and found that the krausen had fallen and there was no discernable activity in the airlock (I know, that's not a good indicator, but for reference there was none). Same yesterday morning, and still nothing last night. I could tell something was happening, as the bubbles on the surface were showing signs of life, and if I looked really close I could see movement in the wort itself (bubbles rising up for lack of a better way to describe it).

My first thought was that maybe I didn't have a great seal, since I didn't actually pick up a bung for this carboy (got it used on Saturday) and just used one of the orange carboy caps with two openings (one capped, the other with an airlock). So I stopped at a LHBS near my office at lunch today (just discovered it's there, yay) and picked up a bung. Got home, washed it and sanitized it, and decided to check grav while I had it open. Sanitized my thief, opened up the carboy, got my sample - it's at 1.010. According to Beersmith, my estimated FG is 1.011.

So...is Nottingham that fast, or did I just way overpitch by putting a whole packet in? The sample actually tastes pretty good, and I'm sure after I leave it to clean up for a couple of weeks it'll be great, but I didn't see anywhere near that amount of activity from the small batch Centennial Blonde I did with Wyeast 1056.

the dry yeast has way more yeast cells than a pack of wyeast. you over pitched that 2.75 gallon batch, you made a big starter.

According to your numbers and the mr malty yeast calculator, you would have probably been OK with a half pack of notty or a whole wyeast. I have done 2 gallon batches pitching nottingham and mine usually bubbles good for about 48-72 hours but I like to ferment in the lower temp ranges around 64. I'm not an expert, but i bet you'll have good beer. I'm curious as well if the speedy ferment makes a difference. In for the experts.

I've had notty finish quite fast for me as well. Usually around 3-4 days though. You should be fine.

Currently using Notty for the first time. Fermenting very fast at 62 degrees in an IIPA.

Effect of Pitch Rate on Beer Flavor
Pitch rates, in addition to strain, temperature, and gravity, make a dramatic difference in the final flavor and aroma profile of any beer. The pitch rate will have a direct effect on the amount of cell growth during a fermentation. Cell growth decreases as pitch rates increase. Ester production is directly related to yeast growth as are most other flavor and aroma compounds.

A low pitch rate can lead to:
Excess levels of diacetyl
Increase in higher/fusel alcohol formation
Increase in ester formation
Increase in volatile sulfur compounds
High terminal gravities
Stuck fermentations
Increased risk of infection
High pitch rates can lead to:
Very low ester production
Very fast fermentations
Thin or lacking body/mouthfeel
Autolysis (Yeasty flavors due to lysing of cells)
With some beer styles, where a complex ester profile is desirable (German Wheat) it can be beneficial to under pitch. Over pitching can often lead to a very clean beer lacking an ester profile (banana). This is a common problem with subsequent generations of Wyeast's Weihenstephan Weizen #3068. Conversely, beers that require a clean profile should be pitched an an increased rate.

@harebearva

Thepack of notty reads" for 1 to 5 gallons"
So, what you are looking at is a regular naughty Notty ferment