Pushing is a bad play unless you hold the Ah or the made flush.

His raise could mean a semi-bluff in which case you are in good shape b/c you hold the Kh, or a made weak flush, or any combination of top pair etc. That flop was a great opportunity for an opponent to run a bluff and it would have looked brilliant if you snapped him off or if another heart came.

Overall, a trickey hand. Since you hold the Kh I would flat call his raise and see the turn. Your flat call may also slow him down b/c he has to fear the made flush. If you improve to the flush, hammer away. If he comes out swinging again on the turn, easy lay down.

Pushing wasn't wrong against a known bluffer or super aggressive player assuming you have a solid read. Pushing is bad against an unknown b//c you will only get called when you are behind.