Super fast fermentation?

I am currently in process of my first batch. IPA with a starting gravity of 1.052. We brewed it, cooled it, pitched it. The lid almost blew off with 24 hours. Not thinking, I racked it in to the secondary after four days. (No activity in the airlock). It's been 7 days total. I currently have a gavity of 1.012 which is on the low side of a final gravity reading. I have been searching the threads and this seams a little quick. I plan on leaving the beer in the secondary for another week or two.
Is this typical?
Thanks

It smells great but it is pretty bitter.

Welcome to HBT!

Your gravity looks good so it was finished with that part of fermentation. A day or a couple of days is pretty typical for main fermentation. BUT you did move it off the yeast cake too soon.

The yeast's job is not only to create alcohol (fermentation) but to clean up off flavors and clear your beer. Your beer will be fine but next time leave it on the yeast cake for a couple weeks at least so the yeast can complete it's job.

Should I add some yeast to correct the problem? There is about 1/4 or more of "cake" at the bottom of the secondary.

No, you shouldn't add fresh yeast. It'll be ok. Just don't rush it next time, though.