Sounds like you racked it way too early and will need to repitch; 3 days is too short a primary for just about any beer, let alone something with a high gravity.
I would buy another packet of Nottinghams, pitch it, and attach a blow-off. Then let it sit for at least 2 weeks (you can replace the blow-off with an airlock once the bubbling simmers down). Once you know fermentation is complete (by taking hydrometer readings on consecutive days), you can go ahead and bottle.
And now we go AG!
On Tap: Nadda
Planning: Extra Special Bitter