I have a single white bump that appears on my bottom lip. it doesn't itch, burn or tingle. i've been dealing with it for the past 2 years. i got screened for every std and it all came back negative. what could it be? i did bite my lip a lot.

Need more specific..: How long have you noticed this bump? What is its dimension and has it grow in size? If not hurting and not growing in size, it could be just a harmless ectopic sebaceous glad (or called Fordyce's spot:, which require no treatment except personal cosmetic annoyance. Of course, it is hard to tell for sure what it may be without a direct look at. So, seek evaluation and counseling timely.