Sorry to hear that you bit your lip, but I am glad that things seem to be healing up and that you no longer have any pain. The lump that you have on the inside of your lip is probably just residual swelling and scar tissue. You will need to give this some time - sometimes these small lip injuries can take several weeks to months to go away completely!
The important thing is to avoid irritating the area more - don't pick at it or bite at it, as this will just delay healing more. You don't need to worry
, though. It will eventually get better, and you have probably not done any significant damage to your lip, nor have you ruptured anything important.
Occasionally, trauma to the lip like this can produce a small mucus containing cyst. Therefore, if after several months, the area has still not resolve or is growing in size, it may have converted into a cyst. A cyst is still not bad news, but they can sometimes be uncomfortable. You would need to go see your primary care doctor
to confirm whether or not it is a cyst and, if so, to determine if it needs to be removed.