I understand your problem. Anal fissure can be quite painful. It is a linear tear in the lower part of the anal canal. Patients generally experience pain during defecation, bleeding and constipation.
I would recommend a few remedies that could ease your pain such as:
A) Consume a high fiber diet like lots of vegetables, fruits, and brown rice.
B) Adequate fluid intake (6- 8 glasses per day)
C) Use of stool softeners (Lactulose)
D) Seitz bath three times a day
E) Use a local anesthetic agents like lignocaine 2% ointment.
F) Anal dilatation done regularly.
Try these methods for a week. If the pain persists you can consult your surgeon for further evaluation.