5NL FR - KK 3-bet pot facing flop all-in donk bet

[daviddem]

Opp is a donk who limps and calls raises with any 2 suited or connected. I seen him show down shit like J6s or 45o. He is 50/0/1 over 20 hands.

I must have a complete maniac image because I've had an incredible run of cards in my first hands at the table. I was running 40/35 or so.

After my show of strength preflop, I am unsure whether he still calls with his entire range but I would certainly weigh it more towards pocket pairs or high cards than the suited/connected trash.

Then comes the flop and the all-in donk bet. Again unsure whether he hit a set, has a draw or an overpair, or even air. So far I seen him be passive with his draws and go all-in with his strong hands though, but here with my image and the bloated pot, I can see that kind of player deciding to go all in on the flop no matter what. What really makes me tick is that if he is thinking at all, he should know I'll bet again if checked to, so why would he donk a set or straight and take the chance that I don't pay him off.

Since these are my first hands at 5NL and I have been doing good so far, I just folded (decided to follow the advice in the other thread "if unsure, fold". Now against such a donkey, I don't think I would normally fold this (read: if I was well into the green at 5NL).

What do you think?

No-Limit Hold'em, $0.05 BB (7 handed) - Hold'em Manager Converter Tool from FlopTurnRiver.com

saw flop

Hero (MP2) ($8.84)
CO ($5.43)
Button ($3.99)
SB ($3.74)
BB ($4.86)
UTG ($4.42)
MP1 ($3.82)

Preflop: Hero is MP2 with K, K
UTG bets $0.17, MP1 calls $0.17, Hero raises $0.75, 5 folds, MP1 calls $0.58

Flop: ($1.74) 7, 5, 6 (2 players)
MP1 bets $3.07 (All-In)

Total pot: $1.74