I was very fortunate in that my ENT listened to my symptoms--which were basically reduced hearing in my right ear and the sound of a "heartbeat" in that ear as well--and decided to do bloodwork, hearing tests, and an MRI so that he could rule out any physiological problems. He did not laugh at me, and I'm so thankful he did what he did, because as it turned out, I do have a small to medium AN on my right side. When he did the MRI, he told me that inner ear tumors are very rare, and he didn't expect me to have one. But I did. Thank God he did all the tests he did, so that I know what I need to do and can make informed decisions about it.
Never stay with a doctor who doesn't respect your opinion or questions. I'm 48 years old and I've brought a family member with me to every appointment so that I can make sure I hear what the doctor has really said and also so that the family member can ask what I forget to ask. You may want to do the same thing. You're never too old to have someone there supporting you.
I agree with everyone so far in that there can be many reasons for what you're experiencing. The important thing is that you listen to your gut and get the right tests--an MRI with contrast, as everyone has said--so that you can have peace of mind and know that you've not left any rock unturned.
Good Luck!
Beverly