More detailed history needed in your case . Are you suffering from constipation? Does the pain started after you passed hard stool? Is it a burning type of pain ? Do you have any skin tag like swelling around your anal canal ?
Next Steps
If you have anal fissure you should Drink plenty of fluid - at least 6-8 glasses of water daily , 5 servings of fresh fruits or vegetables, Ishabgul husk 2tsf with meal or fruit juice twice a day , try sitting in lukewarm water I a bath tub with 10 ml of 5% betadine solution poured in it for 15 mins during bath daily , Apply anovate or Crema L gel locally twice daily
Health Tips
To be confirmed that you have anal fissure you need to visit any Surgeon for detailed physical and local examination.