Thanks for asking the query,
As you have mentioned that you have undergone double jaw surgeries followed by subsequent surgeries
these are all time consuming procedure, traumatic and requires a lot of bone removal.
During the procedure the patient have to open the mouth wide open for a long time so there are chances that the facial muscles
go into temporary spasm after the procedure leading to pain in the jaw while chewing, yawning and wide opening the mouth.
I would suggest you to consult the concerned Dentist
get the clinical evaluation done, if necessary take the x-rays.
Get the analgesics and muscle relaxants prescribed to you.
Have semisolid diet, follow the mouth exercises, avoid wide opening of the mouth.
Hope this helps out.