The basic idea behind Emotional Clearing work is to let feelings come fully into consciousness without the normal interfering actions of the mind, such as resistance, blame, avoidance, acting-out, etc. When you allowed the feelings to come up instead of pushing them away, they went thru their complete cycle and started to clear.
You don't necessarily need to recognize the feeling. Sometimes there's just a big release of tension which is very healing. As you get more into the work, however, you will be able to specifically recognize your feelings, and this is desirable and important for in-depth healing.
From your description, it may be that your feelings have something to do with not being good enough. When you realized that you could perform well there may have been the release of the self-doubt.
Of course, as an artist, you have other options available. Instead of pushing feelings away when you are performing, you include them in the performance/composition. But there are even more sophisticated approaches to using your art as a means to emotional wellness, which I talk about in my book "Emotion and Art" which I would recommend for you.
