Paranoid about brain tumour

... Forget to mention that I am continuously getting ringing in my ears too.

The first thing to say is that brain tumours are rare and even though your grandma suffered with one there is nothing to suggest that is the cause of your symptoms. You should consult a health care practitioner but my lay view is:-

BPPV can give unpleasant symptoms-I have had it - but it can be treated by a physiotherapist with positional exercises and some drugs help too.

tinnitus, as you describe as ringing in your ears, is common and can have may causes.

i suggest you get these symptoms checked out rather than worry you have the most extreme and frightening condition. 

In my life I have had all the symptoms you describe, have resolved them but they are wholly unrelated to the brain tumour I now have decades later. Headaches can be a symptom of a brain tumour but far far more likely to be 

to have other less serious origins.

if however you have obvious neurological symptoms, affecting your speech, gait, awareness etc then you should seek help swiftly. 

I can also add that eye floaters are so common. Had them too, and while there are claims for treatment they are usually left untreated. They are not harmful and have no connection to a tumour. If you are that concerned consult an eyecare professional.

Best to ignore them and avoid focusing on vistas where they are more prominent, like a cloudless sky. You really can train yourself to ignore them and they do not affect eyesight. It is one thing to simply live with.