Removed the corn by surgery twice and stitches...

Surgical site pain and its treatment 
If you had a surgery at any  time then you are expected to have some degrees of pain through the process of wound healing till the full return of the full structure of the incised tissue and to treat the pain you are adviced to take Diclofen 50 mg tab once a day with a maximum dose of twice a day. The occurance of pain after removal of a corn surgically is not a sign of Corn recurrence although it does not mean that the corn will not recure as the corns are highly recurrent and if so you area adviced to visit your treating surgeon 
Required tests 
The occurance of pain could be a sign of infection so you ara adviced to do  CBC to detect any increase in white blood cells count as sign of infection. An ultrasound scan of the wound site to look for any collection or hematoma formation is adviced  
Causes of surgical site pain

• Long incision 
• damage to a surrounding nerve structure 
• Wound fluid collection and hematoma formation 
• surgical site infection

Our advice
You are adviced to keep your wound closed till removal of stitches and do hot pathes for the wound after that to reduce pain