At night I get to sleep just fine, but if I wake up and try to go back to bed, or if I try to take a nap during the day I get sick. I start to fall asleep but my heart starts pounding really hard and I get shaky and dizzy and lightheaded. If I manage to fall asleep anyways I have really vivid dreams and wake up every 10 minutes. As soon as I stop trying to fall asleep the symptoms start to go away. This is really weird. I don't think it's psychological because I don't always feel anxious before I fall asleep. I'm on 20 mg of Brintellix (which is relatively new) and 2 mg of Xanax a day if that helps.