Hello! Thanks for putting your query in HCM. I am a Gastroenterologist (DM).
As you are taking narcotics analgesic
you may be feeling constipated ie straining while evacuation, hard stools.
I think you are suffering from anal fissure
. You should:
1. Take laxative or stool bulking agents like psyllium
fibres to make stool softer
2.Take lots of liquid and fibres in your diet
3. Apply locally in anal verge an ointment containing diltizem or nitroglycerine
4.Take sitz bath
Hope I have answered your query and this will help you. Remain in touch and get-well soon.