Can masturbation or even sexual arousal cause a feeling of being dizzy, lightheaded, or out of balance?

Dizzy over love: I'd hope so... Life would be sad indeed if there weren't people who'd excite us enough to make our heads spin. Embrace & cherish this complex experience. Now, if you actually feel like you're truly going to faint, and other things trigger it also, you might be getting vagal and a talk with your physician about a possible cardiac rhythm problem (anything happen to your pulse?) might be in order.