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Hi Sue, The ringing in the ears is called Tinnitus. It can be a side effect of medications (check what you are taking) or for me, it can also be a sign that a migraine is on the way. It could also mean a number of many other things, depending on other symptoms you may have.
This can sometimes be caused by allergies, infections, and even tumors, but it is often simply something that some people have due to their anatomy (ie, they were born with a pre-disposition to this problem). Sometimes, this clogged feeling in the ear can be a trigger for headaches. As you know, headaches can come on from almost any cause, and some people will have different things that are triggers for these headaches to start. Continued ear pain, hearing loss, and dizziness would all be potentially worrisome symptoms.