I'm Having Really Bad Anxiety Right Now. I Have An

I'm having really bad anxiety right now. I have an unhealthy fear of death. This only happens at night which makes it extremely hard for me to sleep. For this past week I have been going to sleep at around 6 or 7 am (when the sun comes up). This only ever happens at night and when I'm alone. The sun and light never makes me feel this way and I have no idea if this is serious. I have thought about death ever since I was a little kid. When I get scared I think of the nothingness and emptiness. I think that one day there will be nothing. I won't exist and no one I love will exist. Just writing this is making my heart beat faster. This never happens during the daytime. When I get scared I want to pound on things or go outside and feel the fresh air. I try to distract myself by watching TV or by being on my phone. I cannot escape these thoughts. What can I do? I'm not an unhappy person but at night I get overwhelmingly frightened.