Let's face it, 90% of the time painting or creating in any medium can be downright difficult. Mistakes can be plentiful. Attempts go fruitless. Ideas don't work out like we had planned. Our talent and techniques seem to fail us.
So, you are fully engaged and involved in the process of drawing, painting, collaging, etc. Everything is humming along nicely. You are working hard and having fun. (After all, that is what it is all about. Right?) Everything is clicking. You and your brush are one.