First AG Fermentation

So i brewed the two hearted clone floating around on the forums, and everything turned out great except my efficiency was pretty bad, 65%, but it was my first AG on a new eBIAB rig so i'll still chalk this one up to a win.

Anyway, it has been fermenting away VERY rapidly and formed a very nice krausen yesterday, mind you i brewed this 2 days ago, and i looked at it today and it was completely done fermenting and the krausen had fallen back down.

Is it normal for that to happen so quickly? I've brewed a few extract batches in the past and most have tapered off over a 2-3 day span.

Im not worried about it, more just trying to learn as much as i can so i can make better beer. I love AG though, and i feel like it opened up a huge door for making my own recipes and experimenting with flavors.

EDIT:: Forgot to mention I ferment at around 70 because that's the best i can do in my apartment. The two hearted is in my swamp cooler so it is probably sitting at 67 or so in the carboy.

If the fermentation temperature could be 4-10 degrees warmer than the air. (4-10 are the numbers I have heard, but before I used a swamp cooler I measured about 6 degrees) So given the high fermentation temperature the speed of fermentation makes sense. You are likely going to have a fair amount of ester production and DMS flavors. You might want to let it sit on the yeast cake for at least a week to clean that up. Taste will tell.

The temp 67is with the prob on the Carboy and insulated. Water temp is much lower so I'm thinking that the 67 should be pretty close to the temp inside the Carboy so my temps shouldn't be too high for many esters to arise