Second time around!

Hi! My name is Nikla and this is my second time around here! My main issue is drinking Mello Yello soda and eating candy. Any type of candy! Exercising is difficult due to the fact that I have a torn mensicus in my knee. I can walk (for a short distance) and have permission to ride my bike. Running (which got me into this trouble to begin with!), squats and lunges are out for me. I also work the night shift at the local children's hospital, so that is another strike against me! So any advice would be great!