I hope the interview went well! Sometimes the result is not even the most important thing as is the experience of getting to do interviews.

One of the things that i try to keep in my head, always, is that it is a two-way street. Of course, you want the job based on the information you have, but is that still the case when you are actually talking to people?
Of course you can fail at something they throw at you, that is always possible, and sometimes a person is not (yet) good enough for a certain position. There is absolutely no shame in that. People learn and grow, and interviewing is part of that.

And in the end, it's okay to be nervous, all part of that game which you will get out of a little bit better, more prepared and experienced than before you went in.