Hi and welcome.
Yes there is a possibility of mucous retension cyst if it appears like fluid filled cavity. In your case examination of the lesion is very important for exact diagnosis. It would be best if you get it examined by your doctor. If you can take a photo you can attach here.
Let me know if you have further questions.
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Wish you good health.
Thanks for reply.
In picture it seems to be a cyst. You need to follow up with your doctor for exact diagnosis and a small incision may be required for drainage.
My pleasure to help you.