How do you know if you're experiencing sleep apnea? Well, first of all, excessive daytime sleepiness and excessive daytime anxiety combined with daytime sleepiness is one sign that you might be suffering from sleep apnea .. If you happen to snore, it's very likely that you are experiencing sleep apnea. And I should mention that sleep apnea is a very serious health concern. It greatly increases the probability of a cardiovascular event, heart attack, stroke.