Post missed flop AK play - Am I a donk?

[petvan]

About an hour from the money in the 30+3 Stars and I am a bit under average stack with AK in MP at a full table. I open 4X (been mixing up my opens from 2.5 to 4) which is 800 of my ~4200 stack. CO with ~8200 calls and the two of us see 754 rainbow on the flop.

At this point, the pot with blinds is 1900. I have little read on this guy and 3400 chips left. With blinds about to do 150-300, 3400 isn't really where I want to be. I figured with high pockets, this guy is coming over the top on me PF, and thus he likely missed too, or has mid pockets. Given he can very likely put me on mid to high pockets, at at least AJs or so, I make the call to push here thinking my FE is still useful, and I have some outs if called.

He thinks for a while, then calls (with A6s which makes sense at this point, but certainly is questionable PF)

Anyway, I'm not interested in the beat, but rather some tips on how to play AK heads up with a flop like this. I think in most cases, villian is on AK-AJs, and 10's to 7's. I think with AKs, QQ, JJ you raise PF, and AA/KK you mostly raise, and I would also expect in rare situations, people would flat call with KK/AA hoping to bust me when my continuation bet commits me (or I just push it all in for the taking anyway)

Am I looking at this wrong? I tend to lose a lot in these situations though in many cases, I get my chips in with the best hand, but often the edge is pretty small.

Thanks

P