What are the diff. reasons, with explanations pls, for this experience: feeling strong throbbing in my eyes and in my ears in time w/heartbeat. thanks?

Vascular: If the throbbing synchronizes with your heartbeat, this is something vascular. You need to consult your doctor re. this issue since this may signal the presence of an aneurysm.

Headache: This sort of throbbing headache can be due to several reasons, may be your sinuses and middle ears, yes they are one system, or may be another type of headache as cluster headache. Bottom line you need good evaluation, start with your primary doctor who may refer you to other specialities as ENT / Neurology, all the best