How to find out if pilonidal sinus has occurred again

i had a surgery in june 2025 and currently in feb 2026. I don't know what type of surgery it was but the doc told me they cut me open removed the sinus tracts and then stiched everything back and attached a drain near that area for clearing the dirty liquid/blood (it was attached for a week). the area where the drain was attached still hurts a lot when pressed or touched.

the purpose of making this post was to know how to identify if pilonidal sinus has occurred again after surgery because lately I've been feeling a very little bump under my skin near the stiched area which is felt only when i touch it (it doesn't hurt) and i can see a small hole is there on the stiched area but nothing comes out of it.

please throw some light onto this and suggest me if i should visit the doctor on this matter. I don't want this disease again.