I would recommend you have sleep studies done; ordered by a Pulmonologist or a Neurologist that specializes in sleep disorders.
Keep us posted.
I think you need a good, thorough, general physical exam. It might not be sleep apnea per se, but some other type of cardiopulmonary issue. Maybe you don't need a sleep medicine doctor but rather a cardiologist or a pulmonologist. So the primary care doc would be the place to start, and then let him or her refer you to the most appropriate specialist. Good luck.