First time Morde.. went poorly. Very poorly. I was up against an AP Yi (yay blind pick). I would burst him within an inch of his life, waiting for the ult to pop and he'd just meditate back to full while I beat on him. I REALLY hate AP Yi when I have no interrupt. His jungler was also up my butt and I started 0/5.
But the glory that is Morde farming saved me. I was taking both wraith camps and half my useless jungler's jungle as well as mid. I was about 100 cs over anyone else and once we started teamfighting I was putting out the hurt. Still, the only reason we won was a better late game comp and a very fed Ashe (that'll teach them to spend that much time killing a 0/5 player and ignoring the AD carry).
Still I could have done so much better. That was a rough outing. Went 13/5 Brand (or thereabouts) next game to make myself feel better. I hate getting carried. I want to contribute.
Knock on wood I've been on a pretty good win streak. Only 2 losses in my last 15 or so games. I've shifted gears a bit and instead of focusing so much on how to steer the team to a win (which I still don't have enough experience to direct and most people won't listen anyways), I'm concentrating on my mechanics - cs'ing, dodging skillshots, map awareness, warding like crazy, building around the opponents as opposed to just a boilerplate set of iteams, making good decisions (go in, don't go in, back out, stick around for a surprise attack, etc). It's made me a much better player. There is a lot you can do to help your team when you have your own play under control.