Keep things in perspective. Getting in to YC != success. It's one data point. Success = Success. Get your customers to love you. Get people to pay you for you

Keep things in perspective. Getting in to YC != success. It's one data point. Success = Success. Get your customers to love you. Get people to pay you for your product / service. Be better tomorrow than you are today. If you were doing all those things when you applied, that 1 data point doesn't a failure make.