Congrats on your success! You deserve it.
Some people think that they do not deserve academic achievements because things are not as challenging as they expected, but they often forget what they have gone through in order to achieve that success. Sometimes, they also forget how hard it is to learn things.
Even if the exam was unreasonably easy or hard, you should move on. Do not dwell on the past. If you still think that you do not deserve the success, just work hard. Eventually, you will believe that you deserve every good thing that comecomes to your life.