Thanks for the query,
Sutures contain proteins.
There is a possibility that You have developed an allergic reaction
Apply a mild steroid
lotion like desonide
Also take an antihistamine tablet.
This will give you some relief.
Yes it is better to call a doctor for stitch removal.
Please meet a dermatologist
for exact diagnosis.
Let me know if you have any other doubt.
you can ask a direct question to me on this forum, following the below link.
Wishing you a good health.