Don't lose heart - it happens to us all.
Thursday and Friday in the UK was the best weather we've had since winter. The result was that everyone with a pilots licence tried to get airborne.
Now picture the scene on the other side of the microphone. An ATCO who has held a radar rating for a week, at a busy LARS unit doing that as well as arrivals and departures. It was an eye-opener for me and bloody hard work. And at the end of the day I thought the same as you - for a millisecond! It was still something I enjoyed, even if I was working the hardest that I possibly have in my entire working life.
So the answer is NOT to give up - imagine if I felt like that after that sort of day. The answer is to analyse what you did wrong and learn from your mistakes. We're all only human after all.
Stick with it my friend
CM