Twice now and five months apart, I experienced these symptoms: awakened in early morning with a rush of euphoria lasting about ten seconds, immediately followed by about ten seconds of panic like I am going to die. Then, I experienced the same thing about three more times throughout the day (each time). There are no physical symptoms. I take no medication and have never used recreational drugs and I don’t drink alcohol. What do you think would cause this. The euphoric feeling is great but the panic makes me afraid to think I could have another episode.