There are apparently a limitless number of ways to screw this up.
There are 26 pages in the thread below, is that a hint? And if you do a search for "mistakes", that's not the only thread. The best thing about printing is that you can do another one. Getting the film developing down is really the tough part. You'll get it, don't worry. Realizing what went wrong is the main thing.
http://www.apug.org/forums/forum37/4...-darkroom.html