I work in pulmonary / sleep medicine, and I just wanted to share my waaaaayyyy too many years of education. Most people have the misconception that you must snore loudly to have sleep apnea. While snoring and gasping for breath are symptoms of sleep apnea, there are some more subtle symptoms: headaches upon waking (lack of oxygen while sleeping), waking up to go to the bathroom (not sleeping 'deeply' enough that you wake up to go), waking up with a sore throat/dry mouth, insomnia/restless sleep, feeling tired during the day, moodiness, irritability, difficulty concentrating.