First of all, congratulations to all who are accepted, you all deserve a short break.
For every accepted student, there are three or more students received a disappointing news. You too deserve a little break. Please do not take this disappointing news personally, take it nonetheless. There is more work to be done.
This is not the time to second guess yourself.
This non-acceptance does not define you in any shape or form. It does not mean that you are under qualified, over qualified. So, stay positive, do not let it define you, keep on doing what you have been doing in the last hectic few months. In the end, you will find your match.