Have ever your have anxiety or feel depressed about your problem that doesn't exist?

Isn't the whole deal with anxiety that you stress about things that may or may not actually become reality?

At least for me, thats the main way I experience it.

When I was a child the priest on Sunday said that we'd go to hell or heaven when we die and that we'd stay there forever. I got very scared, I don't want to exist forever, I find that a very scary thought.

Later once I grew up I realized that there is probably no god, so this is a non-issue for me now.

The thought of everything we do amounting to literally nothing when we die and forever cease to exist kinda freaks me out
- Does that not make you want to enjoy every moment of your life to the fullest? If it's the only one you get then you might as well spend it doing things that make you happy.
- Personally, I find all the other eschatological possibilities much more disturbing. The heaven/hell dichotomy is unnerving on a lot of obvious levels. Reincarnation seems fraught with neverending suffering. And the idea of becoming a "ghost" or a spirit, forever consigned to haunt some old place is as terrible as it is ridiculous.
  
  I'm looking forward to my hard earned non-existence, thank you very much.

I used to be anxious about my school keeping those pesky permanent records which talk about all the shit I did. I later learned that's not what schools mean by permanent records.

Anytime I'm having a genuinely good day I will get terrible anxiety about halfway through. Things are going too well, something has to be wrong, what am I forgetting?

ADHD leads to a whole new kind of anxiety, even when you have everything you need.

Yes, even as someone without anxiety this happens. This is especially true if I haven’t gotten enough sleep the last couple/few days. Also, it comes with a hangover besides the physical ailments. Lastly, if I’ve been stressed for a long while about certain things and those eventually get resolved, I’ll still feel anxiety/stress for awhile, it’s what I consider burnout as it applies to me.

This is the reason people meditate. People have the ability to imagine stuff that doesn't exist and may never exist or existed in the past. Think about how easy it is to remember some traumatic event from the past. Dwell on it and begin reliving it, feel the sensations as if you are present at that moment. Meanwhile, back in reality, you are safe and warm, sitting on your couch. This way of thinking is extremely common and is the gateway to depression.

Meditation works by resetting your biases so that you notice what is going on right now. It's like a universal solvent for the mind. Don't get me wrong, thinking is important, as a source of creativity, organisation and planning. It's not like you can ever stop thought but it can become extremely toxic to your mental health.

No, I'm mentally stable