That's one of the points rotating with warm and cold water! I would say that maybe the [words=http://www.mattersofsize.com/forum/showthread.php?83577-Length-master-official-order-thread-now-shipping-06-16-2014!!!]LM[/words] session had caused some fatigue already as you stated.
I've also felt at times that the girth enhancement, even wearing a cock ring afterwards, does fade quicker compared to a warm water session.