Thinking about the OP, I am bouyed at the thought that an instructor is requiring better use of the rudder. The least considered flight control needs all the attention it can get. Of course, not being there, I don't really know what the instructor said about the rudder, but I hardly expect that the instructor commented on incorrect rudder use so as to suggest it should be worse!
Alex said:
.....I've currently got 13.7 hours ...... I'm now a crappy pilot.... I'm a bad pilot?
Without wanting to seem negative, and with due respect Alex - you're not a pilot yet, so you can't be a good or bad one yet - relax! I know licensed persons with hundreds of hours logged, who aren't "pilots" yet, they are still just drivers (often 'cause they are really sloppy on the rudder!). If you walked into a courtroom articling for a lawyer, they are not going to call you a lawyer yet, nor expect you to be a pro. Even when you are out on your own in court, you'll still have some very experience lawyers with holding their buy in to your skill. Aviation is the same, give it a chance....
If Alex has the patience for law, and all the overly formal and pretentious goings on with that profession, aviation should be easy to withstand.
You are going to spend a lot of your hours flying a plane, realizing that you could have done better, get used to it. The rest of us have or are!
Wait until you have thousands of hours, and you bounce a landing in front of everyone - and you, and they know that you should have done way better than that! You're at the very front of a long path of learning, and having to rethink you perception of your skills.
Listen to your instructor, and give it time....