After Walking in the Boot ?

I fractured my 4th left metatarsal 69 days ago and was given a sandal with velcro to wear along with an ace bandage from my foot doctor after I limped for 10 days on my foot not knowing anything was fractured.
That didn’t help, so we went with the boot for 3 weeks.
My fracture is almost healed and I am to wear tennis shoes for a month.
The problem is for 2 weeks in tennis I can’t walk normally.
It was like I was still walking like when I was in the boot.
Started physical therapy today and the therapist said the problem lies in the back of my ankle.
I remember telling the doctor that my ankle was swollen in the boot but I guess he didn’t think anything of it.
My question is…..shouldn’t he have given me some exercises to do while I was in the boot to prevent this?
I hope this therapy works for the next 3 weeks…not being able to get around is driving me crazy.
Maybe this doesn’t happen to everyone?
This is my first broken bone so I was clueless as to what I could have done to prevent this immobility.