Hello. Regards from Dr Patil.
As per your explanation & images shared, it is most likely *suggestive* of pilonidal cyst! Following are the symptoms associated with this :-
•Pain which often gets worse when you’re sitting.
•Nausea, fever and extreme tiredness (fatigue).
•A small dimple or large swollen area between your buttocks.
•An abscess with draining pus or blood. This fluid may be foul-smelling.
•You may notice the area is red and feels tender.
Next Steps
Physical examination and other diagnostic test (SOS) such as CT/MRI to confirm it thoroughly!
Health Tips
Naproxen is temporarily helping you from the pain. It isn't the final solution for this. Course of antibiotics + IND if needed has to be the line of management after clinically evaluation.