@loopie_beer is right, give it another week or 2. RDWHAHB. Even when the krausen falls, the yeast is still doing stuff.
Another tip with those buckets, you can put a flashlight against the side, at the krausen line, and see if it's fallen. If you see a solid shadow it's still there. If you just see the speckles of krausen-crud stuck to the sides, its fallen.