Multiple Fractures

I am a 43 year old femal who had a near fatal car accident in July 07 causing right clavical fracture which is now plated; left rib fracture, lung contusion; left femur fracture(rod inserted), right knee fracture, right tibia fractures (pinned), right ankle and heel fractures (plated and pinned), left toes dislocated (wired in). No spine damage!! I was out of hopital in Sept 07 and started physio and hydro theraphy. I am now walking, driving, gardening etc., but sometimes need a cane when I get very tired. I am at a stage now where I do not know how much I can actually push myself in terms of exercise. I used to be very fit before the accident.

I have tried cardio exercising (treadmill) every alternate day but after a week found I set myself back and needed at least 2 weeks to recover! I tend to have a real ache in the lower legs causing me to slow down. The days I drive to work and back, the femur and ankle tend to feel very tired. I have been signed off by my consultant and physio in June 08 but now I feel I do'nt know how far I can actually keep pushing. I still take Paracitamol and Tremadol for the pain may be once a day.

When I start to exercise, the next day, my legs feel like led and I am unable to do much at all. Should I just stick with stretching and no cardio just yet or should I cut down the time I spend doing cardio from say 40 minutes to maybe 15 minutes? How should I go about this without setting myself back. What kind of an exercise schedule should I set myself?

from the information you have given, your UL seems not be severely affected except the right clavicle fracture.
if you wanted to change for cardiovascular fitness, LL exercise might not be the only option, you can try UL exercise also, UL ergometer (UL bicycle that was commonly found in the PT department) would be a good choice if LL training was temporarily unavailable.