I Got My Braces Off In December After Having Braces

I got my braces off in December after having braces for five years. I wore my retainer as instructed, but then in April my retainer broke and I haven't been able to get in to see a dentist in months. I finally have an appointment September 2nd but I am so terrified of getting braces again. My teeth look pretty straight but there are some small gaps. My wisdom teeth are also coming in. I really don't want braces again, what should I do?