I think an ear,nose and throat doc can help. They have these special magnifiying glasses that look like binoculars, that can see the tiniest things. They might be able to see it if very magnified. I've had lumps before so I think if you don't get it looked at you'll drive yourself crazy and your tongue will get sore alway searching for the spot you are feeling.
They have machines that can take x-rays, weird machines I've never seen before until I was there for a problem.
I really believe they can help you.
Get an appointment. It'll make you feel lots better.