one small move, ONE HUGE MISTAKE!

I just finished a game that I lost. After fighting a slightly lost battle I decided to play for a draw in the end game. This particular position was chosen as this is the point that I lost. When I reached this position, I looked it over and realized the move that would most likely end in draw, however, I went against my better judgement and decided to try and force his next move. I was thinking that the one move wouldn't make any difference as I was planning on moving back anyways, I just wanted to try and eliminate any suprises he might come up with and force his move. The second I hit the submit button, I realized what I did,,, I just lost one tempo...(black text is what actually happened, blue text shows what I should have done)I am posting this now to sink in my lesson to myself, and also to hopefully, help someone else in understanding the intricacies of end game, enjoy my pain...