First of all, sorry for posting so much lately :(

For a while now, I've experienced tinnitus on my left ear. It's there every day, more noticeable at night when I'm lying in bed. It's a low noise, it sounds like it's coming from deep inside my head... if that makes sense. Even when I'm not hearing it, if I press a hand to my ear I can still hear it, it just sounds very distant... The fact that it's only on one side worries me. I know two people with unilateral tinnitus and both of them were referred for an MRI because apparently it's a bad sign when it's only on one side. However, when I mentioned it to my doctor, he wasn't concerned at all.

My biggest fear is neurological disease - any neurological disease, but mainly brain tumors - especially gliomas. I had an eye exam last week, they took pictures of my eyes and told me my optic nerves looked perfectly healthy. If I had a brain tumor, this would not be the case, right? I've read that an eye exam can pick up signs of a brain tumor. I also have headaches, usually every day, it comes and goes throughout the day and I know that I have a lot of neck tension and grind my teeth in my sleep... I also get bouts of nausea throughout the day.
I also went to an ENT a few days ago, she removed earwax from both ears and told me to stop using cotton buds. I thought maybe removing the earwax would fix the problem, but no. It's still there and I'm a bit worried to say the least.

Would the eye test have picked up signs of a brain tumor? And has anyone else had unilateral tinnitus that turned out to be nothing or at least nothing serious? I'm starting to freak out a little and could really use some reassurance.