Twitching continuously under right eye for more than 10 days. what could it be from?

Many causes: This is probably eyelid myokymia, which can come on with stress, fatigue, high caffeine intake or for unknown reasons. It generally resolves on its own. Twitching that persists for more than a few months is rare, but could be due to a compressed nerve (hemifacial spasm) which is usually one sided, or blepharospasm, which is bilateral.

Blepharospasm: Or twitching of the eyelid can be quite irritating, though not generally dangerous. Most of the time, no specific cause can be identified. Fortunately, it usually goes away on it's own. If not, a variety of treatments are suggested but none seem to be universally efficacious. I would begin with an eye exam to make sure there is nothing else going on. Stress is often a component.