thank you for posting your query.... you have not told for how long you are having this small lump....in some individuals, an extra fold of skin occurs in the ear but generally does not cause any problems....and in some cases it might be big enough to cause mechanical obstruction leading to ringing or slight decrease in hearing... however you have mentioned that it is painful on touch sometimes...so it needs proper checkup... so do provide those informations that i asked for... and you can consult an ENT specialist for a thorough checkup and investigations to fing out the cause of ringing in ear.... hope that was helpful... regards