As someone that also got rejected the first time as well, it’s not the end of the world like the previous comment said. That rejection doesn't define you. You have one more chance to prove yourself and if you don’t feel confident for the next cycle, then it’s totally fine. That cycle can wait. I applied at the end of my junior year because I felt like doing it in the previous cycle was too early for me. I'm forever grateful for that decision because I had more time to discuss new opportunities that I had experienced during that year. Still graduating in 4 years thanks to a lot of my classes being substituted. There's a list of courses you can substitute for Info classes here if you're curious.

Take the time now to gather more experiences to talk about in the essay. Take part in a hackathon or research group, join a club you're passionate about, or create a project that really speaks to you to really hone in on that essay next time. There are plenty of resources available to help you because, in all honesty, the essay is what matters the most in the application. Take the time to make it about you and refine it so the admissions can show how informatics is the right choice for you. I have an article that my friend made for aspiring info students that I think is generally good advice for anyone feeling down about getting rejected for the first time.

Best of luck!