The broken boy and his mystery leg

So today marks a week and a half of jack having two hairline fractures in his tibia,so today we headed in to the fracture clinic for an x-ray and a check up. I was guessing they would have to put on a new cast since my silly broken boy has been running in his cast! Yep that's right running! and jumping and all around just not realising he was broken. So in we went from one long line to another. Headed to x-ray where he did amazing! Only a few tears And he even smiled for the camera! Then back to the clinic for a check up with the dr. We had the nicest dr. And she gave us some interesting news. It's not broken! Huh? I'm fact she doesn't think it was ever fractured! Oh my! So we take of his cast which he was only Slightly upset about and do a check up. The dr. Said it looked great, she felt around jack showed no signs of pain so now the test to walk on it. As soon as I put him down he was screaming and crying owie and refused to try. So we waited a few minutes and finally got him to take one step where he promptly  collapsed. After almost 2 weeks with a cast and possibly no actual fracture he's still not weight bearing. The dr. Being very confused when and checked with her boss. They agreed something's wrong but they don't know what. She has never seen a kid react like that to walking so back she headed to chat with her boss. They decided to put the cast back on and wait 2 more weeks. They are thinking he has possibly damaged his growth plate? But to test that they have to do a CT and they try not to with kids.  She threw around a few possible things with big words that I have no idea what she is talking about. But overall they are just going to wait. So jack now has a new purple cast ( his choice) and his only instructions are to walk and play as much as possible on it, should be no problem for him! We aren't sure what's going on but would appreciate all the prayers we can get for him. Hoping its just a fracture that no one can agree on.