hello and welcome to HCM forum,
i am glad you posted your query, first of all i would like to inform you that the lump which is now formed on the inner surface of your lower lip, is nothing but a fibrosed,healed tissue. you have not mentioned about its consistency or if their is pain associated with it, i assume it is painless and firm in consistency.
i would recommend you to avoid biting over it, as healing will be delayed, if you bother it too much.
use an antibacterial (betadine) mouth wash twice/day ,practice this for a week.
but , even if does not disappear after a week, then kindly visit your dentist for a check up.,
i hope i answered you query,
i wish you good health.

Hi,
According to your problem,insect bite such as wasps, bees and fire ants can all cause swollen lips.Its venom irritates your skin can produce allergic reaction. It may be very minor and fleeting or can a sign of a life threatening condition called anaphylaxis.So, clean the site of bite with soap and water, can help you stave off infection.Apply a cold pack to your swollen lip for 10 minutes at a time,cold can minimize pain from the bite.Take a oral antihistamine, medication stops or blocks the action of histamine and both relieve itching and relieves swelling. and also I would strongly advice you to visit your doctor to identify the problem and treat it accordingly.

Have a nice time... take care

Hi,
The lump if hard and painless is mostly a healed connective tissue at the site of the injured/infected area. Please do not irritate it further by rubbing or biting on it as it will take more time for healing if you continue to do so.
If after a certain time period it does not resolve then i would recommend you to visit your dentist for the same. If required it can be excised and sent for a biopsy to be on the safer side.
Regards