I think you should have raised this flop, you will then often get to showdown cheaply and may not have to put any money in. You have a lot of fold equity by raising this flop.

I don't know why you call this turn if you are behind a K and a flush draw to a 9. You are getting 4.25:1 on the call and you don't have implied odds if you aren't betting this when checked to.

You also have reverse implied odds which are very high when you make the flush and lose.

I let this go on the turn played as you did. If I did't I bet this river when checked to.

True