What your experienced was rigor. In medical terms rigor is an abrupt attack of shivering and a sensation of coldness, this is accompanied by a rapid rise in body temperature and often marks the onset of a fever.
I do hope that you have been back to your doctor as advised by ER. It is likely that the if you have a bacterial infection, the antibiotic you were given was not the right one. If your condition is caused by a virus, the antibiotic will not work.
Your doctor will be examine your ears and throat for any infections and prescribe what he feels is likely to help.
In the meantime, keep taking the pain relief medication as directed on the packet and also do steam inhalations. Steam inhalations will help to loosen the congestion that is causing the pain in your sinuses.
In a bowl, pour very hot water. Put some Vick or olbas oil in if you wish. Lean your head over the bowl and cover your head and the bowl with a towel and inhale the steam through your nose and exhale through the mouth. Do this 4 times a day for a duration of 10 minutes each time (my doctor advised me to do this when I had a blockage that was affecting my sinuses and ears). Take care not to get scalded.
The doctor may prescribe a nasal spray and some decongestant medication, but this is not suitable for everyone.
Hope you get some relief soon.
So sorry you are feeling so bad.... An ENT can closely examine your ears to determine the cause of your pain and nausea. Some time ago I had problems with my ears and they found a piece of tissue in there!!
You never know - it could be a fungal infection causing you all this trouble.
As for the shaking - I tremble with pain. We are all different -
Wishing you a good outcome