Hello and welcome to Healthcare Magic. Thanks for your query.
From the description of your symptoms - a swelling with a "puncture-like mark" in the centre and the semi-firm consistency, it is likely that you have a sebaceous cyst
. This is not an uncommon swelling but there is a possibility for sebaceous cysts to get infected and become enlarged and painful - in which case surgical excision would be the treatment option.
However, you need a proper physical examination to find out what exactly the swelling is due to. Since you say that the swelling has been progressively increasing in size, I would advise you to see a doctor to have it checked.
Wish you all the best.
Dr. Sheeba Stephen
Emergency Medicine Specialist