ILLUSION OF CERTAINTY

In my experience, nothing is more decieving on a chessboard than the illusion of certainty.
take this game for example.


going through it , its like I played in very different modes. may be a case for me to get checked for multiple personalities at this rate to say the least. I have picked through a few critical moments where I think snatched defeat from the jaws of victory. the full game is at the bottom

on move 19

• black has won the exchange.
• blacks rooks will dominate the soon opening e and f files
  
• Whites dark squared bishop is hemmed in by its own pawns and the oncoming e and f double pawn push.
  
• whites knight is too far away from the action.

this positional analysis in my opinion has white winning.
at this point the plan should be simple, advance the pawns and consolidate the win for black.
on move 27
the advance b6?? is poor cos it surrenders material (a pawn) for no good reason.
on move 32
I should attempt bXc5. however my choice of action is doomed due to the three pawns on the a and b file.the false security at this point evaporated along with the illusion of certainty.
this loss hurt.
lesson learnt, stick to a plan of action and cold bloodedly kill the game when you can.