Sometimes, muscles get stiff from not being used. You might talk to your doctor as there may be some exercises you could do while sitting, to regain range of motion, such as tracing the alphabet with your toes, making circles in the air with your feet, rolling a ball with your feet and others. When I was in rehab, they even had me pick up marbles from the floor with my toes and move them to a small container.
These exercises could help take away the stiffness. Of course, you should never these things until your doctor says it's safe to do so.
Oh wow, both feet? That's rough. It's hard when you have one and you have to baby that one but you still have the other to lean on, but both? How do you get around? Having both ankles injured would likely prolong your recovery time. I would give you a time frame of 5 to 12 weeks to be back to normal. Are you on crutches?
6 weeks
It usually takes 5 to 14 days to recover from a grade one ankle sprain. This is when slight stretching and damage occurs to the ligaments. With a grade one sprain, there is slight instability, pain, swelling, joint stiffness and trouble walking. Grade two sprains can take 4 to 6 weeks to heal.
I would give it a few more weeks, then, if it is not better, go back to your doctor.