Hehe. Well, that's just usual. You'll see that you waste the most time with really silly mistakes.
Just some days ago I wasted alot of time hunting a bug in my "snap to grid" method. Actually... everything was perfect there it was my text printing routine(!) wich reseted that opengl stuff and I had simply forgotten that - doh
Remember that the PC in 99.9999% of the cases exactly does that what you (or 3rd party apis) tell him to do. If there's a bug and the obvious places aren't the reason, check every
single step carefully.
Oh and enable file extensions for the explorer - that avoids alot of confusion. It should be somewere under view->directory options (or so) and it's called "hide file extensions of known file types" (or so)... disable that and use the "details" view. It's much nicer then.
15 is a good age to start this stuff imo oh and excuse my manners - welcome to the board