Thanks for the query.
Without examining the swelling, it is difficult to comment on the nature. A soft swelling may be a lipoma whereas a firm one may be fibroma. Sometimes, it maybe a cystic swelling.
Next Steps
You need to consult a general surgeon for this swelling. If the swelling is persistent or causing symptoms (like pain) or seems to be of doubtful nature (after examining), a small surgery may be needed.
Health Tips
Sometimes a secondary infection may occur which can cause redness and increasing pain, in which case antibiotics may be needed.