Random ear pain may be from eustachian tube dysfunction because of a cold or congestion but more likely it originate from the jaw joint, more information would be helpful in determining the cause.

Hard to say. Ear pain can come from many sources. You can have pain related to ear infections, eustachian tube dysfunction, temporomandibular joint arthritis, throat infections, neck problems, and others.

There could be many causes; however, this is outside of my expertise. If you're concerned and would like to investigate further, I'd suggest that you see your primary care physician and/or an Ear, Nose and Throat physician.