flopped set - now what?

[forssell]

10-25 blind 10-handed game. Table has been running loose-passive preflop for the 5 orbits Ive played, this is surprising. I havent played one hand to flop and I´m waiting for a hand better than 46o to pop at these limpers and take it down pf.

I get 77 on BB. Utg+2 limps, mp limps, CO limps, button limps sb completes. I make it 200 to go. Utg+2 fold, mp calls, others fold. Mp is REALLY loose pf, but seems actually decent postflop. Pot 500. Flop AK7 cc. Mp has 2k left, I cover. I obviously have the nuts here, but I don´t see villain having any hand that could give me much action, other than a sf draw. So I tried to show weakness and bet 275. To my delight/surprise villain raises to 550. Pot 1325, 275 back to me and villain has 1450 left. NOW WHAT?

Im thinking about this and this does seem uninteresting to me, a clear push. Well, I pushed, mp used all his time, announced A7 and folded and told I had AK. Then a hand later he said he should have stacked there. I got pissed I left 1450 in his stack and cursed my small flop bet. Guess I´m still pissed cause I´m posting here. Anyway, does anyone play this differently? I mean, I knew this guy was LOOSE, but 200 pf with A7?