Here I had a won game (or at least a draw). All I had to do was to wait for a lull in the checking, start checking myself till I get into a queen exchange position, and I'm a pawn ahead plus king is centralised.

Problem was I became complacent and didn't really think where I'm moving my king. In one fell swoop I went from elation to deflation...

black had many options to play a lot better due to the mistakes of white

I missed the Qxc3 on move 23 - and of course the Kd8 at the end. 

Another brain fart. I don't know what I was thinking when I played 50.h4 instead of h3.

Actully, upon reflection, it would have been a draw.

no, im sure if u had played Qxc3 move 23, black seals the victory