Ear wax helps keep the ear canal moist and clean, but for some it becomes thick and hard. At times it can completely clog the ear canal.
What happens with impacted (medicalese for clogged) ear wax is that the transmission of sounds is impaired, so it is more difficult to hear. Many patients also report dizziness and nausea. This is most likely due to pressure on the ear drum, which in turn activates the inner ear built in gyroscopes or semicircular canals.
Other nasty things can end up in the ear canal, either by some awful stroke of fate or, in the case of toddlers, intentionally, just to place something where no man has gone before. I have over the years seen live and dead bugs, broken off Q tips, pieces of chocolate, nuts and cookies, toy parts and some unidentifiable objects.
If a bug flies in your ear or you wake up and happen to feel something moving in your ear, you can use a dropper to put some mineral oil in the ear canal. This will suffocate the hapless insect, which eventually might come out in pieces. What you never, ever should attempt is the fateful Q tip insertion. Q tips are not made to be put into your ear canals, only to clean off the outside of the ear. They can and will break off, leaving a sharp wooden object inside your ear canal. They often will rupture the ear drum and in cases where excessive force is applied, can even permanently damage your hearing.
If you are concerned about whatever it is that is in your ear canal, go to the emergency room or see an ENT specialist. Using special tools, most objects can be removed. Younger children often will require anesthesia in order to remove things, but there are definitely cases where I have been able to remove things easily and without general anesthesia.
For impacted or clogged ear canals, you can buy Cerumenex which softens and partially dissolves the ear wax. This takes days and sometimes a week or so. The canal can be irrigated gently with water, but this should only be done by a medical professional. If there is not too much wax, the wax can be removed by your doctor piecemeal. You will feel better right after the wax is removed.