on mouth opening is not sufficinet to make diagnosis. Might be joint involmnt, along with the medication provided, try few physiotherapy
and mouth exercises. As in- keep your 2 fingers in a vertical manner on to the teeth and check whether you can open your mouth till vat cms and then keep on adding icecream sticks (horizontal ones) or try to open the two fingers. Keep a check that way. Do this only when you feel easy and comfortable, do not force urself for so.
-warm saline rinses in the morning and evening may help
-next go in for clinical diagnosis.