Sitz bath / steroids
Sitz baths with warm water with or without epsom salts is helpful.
There are many steroid sprays (epifoam, etc) that are soothing and inexpensive. The main thing is the passage of time. The wound with re-epithelialize (cover over with skin) quickly, relieving much of the pain within a few days. Pain that lasts for weeks is unusual and should be checked by a doctor.