From the medication which you are taking currently, it seems that you have paid a visit to your dentist.
1)after seeing the pictures you have included along with your question, it seems that it is highly unlikely that osmf would have involved your submanidibular lymph nodes.
2) Yes, osmf can be treated in early stages by
-Removal of adverse habits like gutka, tobacco and pan chewing.
-And intake of sm fibro tablet, lycopene rich food like tomato etc., and corticosteroids gel.
Next Steps
You should consult your dentist immediately if possible, if you feel that you have restricted mouth opening. Till then avoid the intake of any form of pan masala, gutka, tobacco.
The medication you are currently taking can be continued.