Exercising after a car accident

I was recently in a car accident at the beginning of December and had to stop all physical activities to allow my body time to recover. My neck is mobile again but I still feel pain in my lower back (the right side where the impact happened), I am not too worried about this because I know it is normal after an accident and even sitting before would cause great pain. I did a lot of stretches for my neck and have been using the recumbent bike three days a week for two weeks. I would like to get back into FB if you guys have any recommendations. I've done FB fit in the past and FB XT but I think my body is not ready for those just yet.