Hi, welcome to HCM.
If your ulcer is treated, you still could be having erosions inside. keep in mind that ulcers always don't burn. They can ache, cramp and even squeeze.
You may try a course of antacids like Ranitidine
300 mg twice a day for a week or two and then see the response. If there is no improvement, then we can think of other problems.
You may consult a Gastroenterologist
if you do not respond to conventional OTC antacids.
all the best.