Dear Leespring,
Welcome to HealingWell, you've found a great site. Oh, and don't feel silly...I was just in a tree on May 28th (don't ask) 
Bummer about the break! But, I do like to put a positive spin on things...better to break a bone instead of a ligament. Ligaments heal 3 times slower than breaks. But in all...it stinks nonetheless.
Do you know the specific type of fracture? Transverse, Compression, Comminuted? Did the bone shatter? Break into pieces? Or a complete clean break?
Well, to make you feel better...you've been healing quite a but already within the past 3 weeks! Hoorah! So the bone is now at a point where it has formed a callus natural splint. And that contains: Calcium, Phosphorus, and osteoblasts.
***So there is a clue on supplements to take now and for as long as you see fit...a Calcium plus Vitamin D supplement with Phosphorous! Glucosamine & Chondroitin too you can supplement with if you're not allergic to shellfish, and Gelatin for joint mobility.
And when you are totally healed from the fracture and the cast is off...you'll start PT. From there on in, walking, keeping a normal weight to free the knees of excess body weight, weight bearing exercises and supplements like above will keep a lot of problems away.
So how are you doing? Is there much swelling?
Do you have anyone that knows how to find the pulse in your foot? Just to make sure there's no compression problems & the blood is flowing nicely.
Any weird numbness, tingling, coldness, turning blue of feet? Wanna make sure that you have feeling in your toes too.
Really glad to have ya here. Write back soon.
Sincerely,
erin