Two horrendous bets

On Saturday night, I had a poker marathon of sorts -- 77 hands, in roughly two and a quarter hours of play. The reason I played so long is that I got behind early and was trying to get back to even. I lost my full starting stack of $40K at the first two tables I joined; I recouped some at the third table, but not enough. Looking back at the hand histories, I see that I only played really badly at the first table. Two horrendous bets did me in.

horrendous bet #1: on the river, with only a pair of kings, I bet $13K, and lost to a two pair of kings and queens; the river card was a queen

horrendous bet #2: on the turn, with three kings, I raised an $11K bet by $300 to go all in, and lost to a king high flush; the board had three clubs at the turn

delta: $-36,300
balance: $858,938