Brief Answer:
Read below.

Detailed Answer:
I read your question carefully and I am sorry about the symptoms that you are experiencing.

Unilateral hearing loss like in your case can be due to many different causes, such as viral infections, vascular occlusion, inflammatory disease, tumor etc. However in a considerable percentage of cases the cause can not be identified, frustrating but true. Since you mention to have had an MRI I am assuming it found no trace of some of those conditions I mentioned (inflammation, tumor, infarction). I don't know what other tests you've had, usually blood tests for inflammation, antinuclear antibodies, vascular risk factors are recommended, so you should check your documentation for that. However even if they weren't done and are done now, you should be prepared for the possibility of nothing turning out to explain your symptoms.
Regarding your other symptoms most of them in my opinion are in the setting of Meniere disease, which explains the humming, nausea and dizziness. Actually Meniere would explain the hearing loss as well, but it's usually progressive not all of a sudden like you describe it. A low salt diet, avoidance of caffeine and alcohol, may be of help in preventing dizziness, also medication like diphenhidramine or meclizine can alleviate it.
As for the tingling left arm I don't think it's related as in case of adjacent brain lesions symptoms would appear on the other side, MRI would also pick it up, it might be more of an anxiety related symptom.
It is difficult to comment about the swollen face and your comment on one side of the nose getting larger, since I can't examine you and make comparisons between follow up visits. I am inclined to think that the nose thing is nothing serious, while for the swollen face in the morning a routine heart check up and blood tests for protein concentration, liver and kidney function, thyroid function can be made just in case as probable causes of swelling, probably nothing serious though.
Regarding the headaches, it is not uncommon in migraine patients to develop chronic headache with the passing of the years. At times migraine can be related to some of the symptoms you describe such as blurred vision, tingling etc. You seem to be under no treatment for headache prevention. I would suggest to try prophylactic treatment. There are many alternatives, but I would go with amitriptyline, which is one of the most common preventive drugs used and furthermore is often useful in alleviating some of those ear related symptoms such as humming and dizziness.

I remain at your disposal for other questions.

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