I am sorry that you are in so much discomfort. Migraine headaches can be painful, debilitating and disabling. As you know, many people suffer from them. A migraine headache usually consists of a pounding headache, nausea, vomiting and sensitivity to light. Treatment is aimed at relief of the symptoms, usually to prevent or stop the headache and to control the nausea. You should be examined by a neurologist, if that was not done already. Although the exact cause is unknown, there are certain trigger factors for migraines, that you should be aware of. They are, changes in hormones (menopausal), certain foods, stress, sensory stimuli, changes in environment (weather changes). Do you have a family history of migraines?
In your case it sounds like you may have sinus congestion contributing to the stuffy feeling and the cough. However, you have been under care of ENT doctor, which is good. Now I do recommend neuro evaluation, as I mentioned before. You will need CT scan and MRI of brain to rule out any tumors, aneurysms or other brain abnormalities contributing to your pain.
You really need to get to the root of the problem so that proper treatment can begin.
Can you please tell me the medications that you are currently taking.
Over the counter medication can be used, such as tylenol or ibuprofen, but you probably would benfit from a prescription medication which is stronger. Certain antidepressants are very effective as well.
Look at the website below for more drug therapy.
It is so important for you to try to control your stress and to do light exercise on a regular basis, as well. Take warm baths and do things that you find relaxing. I would also suggest that you avoid dairy products and cheeses, especially, since they cause increased mucous production.