Could masturbating too much be causing my eyelid twitching? I have had eyelid twitching a few months. I don't feel stressed.

Muscle spasm. What you describe sounds like a common condition called orbicularis oculi myokymia. It's a type of spasm in muscles around the eye. It tends to present in times of stress (no known relation to masturbation). It can cause the vision in that eye to vibrate, as well. If symptoms are severe or not resolving over time, you should see an ophthalmologist.