So, I just had my lesson with Greg Niemczuk.
I started with the Humoresque. Even though I know it's not a performance I was very nervous at the beginning and messed up in a few places. After the initial playthrough we talked a bit about the piece and what to do to improve it but also about technique and how to approach practicing. We went over a couple of spots that were giving me trouble and he provided some tips on practicing it.
Then, I played the Bach and then I also messed up so much he even stopped me and we focused on that spot for a little. He asked me to divide it into voices and practice it separately. After that, I continued playing to the end of the piece and that went fairly smoothly.
I think he is a great teacher and had many insightful remarks about practicing and technique. I might take more lessons with him in the future but I think for the moment I need an in person teacher that I will see more regularly and work on all the little issues.
Thanks to everyone for your encouragement on this thread!