You are not alone. Misery loves company, I guess, but I get some comfort knowing I'm not a freak of nature with my rabid obsession with my oral cavity.
Let me share a few thoughts and experiences, in the hope that they may help at least one person.
1.) I, for whatever reason in my brain wiring, have an rabid fear of any cancer. A therapist says I have a flavor of OCD, and I think I have a touch of hypochondriasis on top of it. Because I dipped snuff for 25+ years, the main target of my fear is my mouth.
2.) There are literally countless causes for lumps and bumps in your mouth, and very few of them are serious, like cancer. But I've learned that the last thing you should tell a person like me is "Don't worry about it". Might as well pour gas on the fire...makes me mad as well as worried.
3.) Some people's tolerance and ability to ignore issues with their body is pretty strong...mine is very weak. It's especially hard when it's something as prominent as a lump in your mouth.
The best advice I can give:
1.) Your worry is not unfounded. It may be excessive, compared to the "normal" population, but it is what it is. If you can find anybody (a close friend, a therapist/counselor, etc.) who is non-judgmental and supportive, then embrace them and talk about your fears.
2.) Find a good dentist who listens to your concerns with that same non-judgmental approach. Don't be ashamed or afraid...admit to your dentist or doc that you are obsessive about oral issues, and that you freak out over bumps. General dentists are good at seeing "bumps", but frankly that's not the focus of their practice. Mine was very conservative, and referred me to an oral surgeon right off the bat, even though she didn't think it was anything serious. Oral surgeons, more than general dentists and ENTs and GP doctors, have a lot more knowledge and experience with mucoceles and other oral pathology.
3.) Education is key. This forum is great. I know that the internet always throws in the "cancer clause", but still you have to understand your body. The oral surgeon I saw is fantastic. He knows how I am mentally, as well as my history. More importantly, he has taken time to sit down and explain/teach me a lot of things about the oral cavity...even pulled out a plastic skull one time. More over...he says to come back any time I have any concerns or issues ( I just took him up on that recently...had a bump spring up on my hard palate...we took it off and had it biopsied...sialadenitis). That being said, don't run off to the doctor every time a bump pops up, but if you're living in mental anguish...by all means go get checked.
4.) If you do go to your dentist, and aren't satisfied with what he/she is telling you...get a second opinion and/or insist on a referral to a specialist...in the end, it's your mouth.
Now it's not cheap...every time you go to an oral surgeon, or even your dentist, it's $$$$...and there's no such thing as a "great" dental plan. I go back to the "mental anguish" thing...would it be worth the monetary investment for some peace of mind ??
Wishing you all peace of mind and good oral health.