22s - AK, TPTK, bet, raise, coldcall?

Level 1 of a Party 22. I open limp A[img]/images/graemlins/spade.gif[/img] K[img]/images/graemlins/heart.gif[/img] in EP, LAG directly behind me calls (we were only 6 or 7 hands in but he'd already raised and called too much with weak hands), MP calls, LP calls, BB checks. We all have ~t800.

Flop: A[img]/images/graemlins/diamond.gif[/img] 9[img]/images/graemlins/club.gif[/img] J[img]/images/graemlins/club.gif[/img]

I bet t65 into the t85 pot, LAG raises to t130, MP coldcalls, folded to Hero

I was confident there was a good chance I could double up off of the LAG. His raise could mean a lot of things, but a weaker ace was most likely. Should I worry about the coldcall from MP? This was the first hand he had been involved in, so I assumed he wasn't too loose? How should I play this from here? Is the open limp with AK bad?