Just thinking about how your feeling and reading your description gives me a strange feeling in my stomach and chest! Not a pleasant feeling I am sure.
Any ideas about what started the negative feelings/thoughts? Have you done a mood tracker? I know it feels like going backwards, but really it's just a sign that something needs ur attention. Usually there really is a reason for "existential angst" ... something tangible and real. Being aware helps and remembering you have a whole toolbox to help you manage. Sounds like you already know that anyway. I'm sorry you are feeling badly.... maybe continue to vent here as much as you need/want. We are always here to listen. Thanks for trusting us with ur vent.