Brief Answer:
THough it may be a tumour but less likely , better to ger an MRI brain

Detailed Answer:
Hi and Welcome to Ask A Doctor service. I have read your question and here is my advice.
These symtpoms may be caused by many diseases like problems in the ears, brain problems, drugs , or many blood disorders.like throid, electrolytes , low HB , and many others .
Brain tumours present in many different ways.They may present with headaches that is progressive and more in the morning.Headache specially increase with cough .They may also present woth seizures and weakness .sometimes present with irrelevant talks .Slight imbalance diziness maybe caused by Brain tumour but is caused more commonly by other reasons then tumours .
So I mean to say that the possibility of brain tumour cannot be ruled out but here but it is less likely. Other causes like ear diseases , or minor stroke in the brain ( more common in this age ) , or age related changes in the brain or other brain disorders like hydrocephalus, sub dural heamtoma are also possibilities . ears diseases , or your thyroid probelms all may causes such symtpoms .
It's difficlut to say what may be causing your symtoms but the best approach will be to get an MRI of the brain with brain stem to rule out brain problems .
I am sorry to hear about your problem and disease of your wife and I understand the difficulty of the one who cares for patient with dimetia .But Lets hope the best .Discuss your issue with your doctor and get an MRI along with blood tests and ENT specialist opinion for your problem .
Hope I have answered your question. I will be glad to answer any further question about this. kind Regards Dr Rahman

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