Two full turns is about 3/4 turn past the max on the specs I use (from Brownells):
Minimum 90 degrees, continue until indexed, maximum 450 degrees total. Since your device doesn't appear to have a specific "top" or "bottom" I would have probably turned it one full turn and left it thereabouts.
Since you got yours installed with no obvious damage, it would seem okay. The cupped crush washers give, and I don't think (short of completely flattening them) that it will hurt to crush them past spec. As long as your threads didn't strip and you device isn't bunged up, you're GTG. You said you didn't clamp the barrel so it's doubtful you put that much torque on the threads.
ETA: I remember this photo from your bayo lug thread. I take it you installed the muzzle device before you started cutting on the lug? Did you ever get some bluing on that? How does it look now?