So while working on my game, Paper Flight, I discovered something today.  I had completed 4 of the 18 tracks used in the game when I stumbled upon another way of creating the different parts of the tracks; it would cut the time needed down to barely a fraction.  Instead of seeing a few more weeks of work on the race tracks alone in front of me I should have the tracks done by, say, tomorrow (leaving mini-games, trophies, high scores and unlockable features left).  Of course I'm happy.  Overjoyed even.  I'm also incredibly mad at myself for being so stupid as to not have seen the method a couple of weeks back when I started the track initially.  Oh well, I guess it's a lesson learned.

I wonder if professional game developers go through this...

Been there, done that, felt the same way :P the bipolar effects of programming.

of course we do, every day.

and it's not just us - it's everybody in every creative and technical medium.  it's a natural part of the process.  and one of the parts that makes it so exciting and fulfilling :)
learning is life.