flopping small boat in shorthanded play

[moneytoburn 0]

Playing 4 handed Ohmaha 8. I am the big blind and call a raise from the cut off with A 6 6 4. Flop comes 6 K K. I check, villian pots. What is play here? Was the check on flop correct? (Villian was loose aggresive preflop, but would play accordingly on flop). If I do pot it back to him and he comes over top what is play there? Is it a insta all in?If he does have K x x x, is it right to want to get my money in?