Hello. Hope you are doing well.
Your concerns seems to be suggestive of Temporomandibular Joint Disorder, which affects the joints of the lower jaw. There are different types and causes. It will be best to visit an Oral and Maxillofacial Surgeon (as they specialise in TMJ) near you for getting a thorough evaluation done and get treated accordingly.
Next Steps
Visit an Oral and Maxillofacial Surgeon as soon as possible
Health Tips
-Have soft diet.
-Try to avoid your mental stress since that worsens such conditions.
-Continue applying diclofenac gel followed by moist heat over the affected joint area.
-Do not try to do unnecessary exercises, your Oral Surgeon will give you some specific exercises. Perform those.