I'm not necessarily the most healthy person, I'm skinny and I try what I can to be as healthy as I can. However, for the past few years, things just seem to be getting worse. I've been so stressed and worried about everything, which has started to take a toll on me. My memory is failing, my body shuts down at times, I have a hard time falling asleep, and an even harder time waking up. I used to just sleep a fine 8 hours and be up and ready to go, but now I'm in bed for at least 12 and being so tired through the day. Routines usually help get things into place, but nothing is changing. With each week that goes by, nothing is getting better, and I am getting medical attention, with a test coming up soon, but there are times I just feel terrified. I'm scared that one day I'm going to sleep and never wake up. I'm so tired and scared, I have such a hard time getting stuff done around the house because of either my exhaustion, will, or attention span. I don't know why I'm writing this other than to get it off my chest. I don't know what to do anymore. I'm lost.

I feel so sorry reading this but please don't give up!
I'm glad to see that you've writing that, also because (like you said) removing a weight from your chest is a good thing.
Now, please do things calmly, you have time and you don't have to stress yourself, everything's gonna be alright.
Just take your time, why do you worry? Just breathe and don't try anything.
Sometimes sleeping more doesn't help at all, you tried to sleep 12 hours but what about trying again to sleep 7 or 8 hours?
Don't feel terrified, I know it's maybe a dumb thing to say but please try to relax, just think about breathing and everything's gonna be okay. Don't get scared just because trying to do things around house make you tired and exhausted af.
Try to focus on eating healthy and taking care of yourself, can you? And once or twice a day, try to just sit down and breathe deeply, + keep writing here, talking about it maybe can help, mh? I don't know if what I wrote can help you, but I hope to be able to do something for you.
Also, remember to drink water throughout the day :(

+ If you're lost, Dollars will help you find the way

I appreciate your words of encouragement, and I suppose I should clarify a few things. I would never do anything that would cause my body harm on purpose, if you get where I'm going. In regards to sleep, I've been setting multiple alarms to try to wake myself up, but I happen to sleep right through them despite how loud they are, and when I finally wake up, it takes a lot out of me to even get out of bed. Seeing that I created this post when I was really tired, I could've probably elaborated a little more, which I apologize for any confusion. As for worrying, I can't help myself. It usually comes in the form of overthinking decisions and engaging with others. Though, as previously mentioned, I am worried about my health in general as well. Picked up yoga recently to try helping me calm myself while also getting in some small form of exercise. For now, it's just a waiting game to see if I get any better.

This may not work for you, but in terms of sleep, try setting a more natural tone to wake up to. Instead of a crazy alarm that sounds like a nuke is about to drop, try using the IOS Bedtime app. They have natural alarms like birdsong and gently crescendo-ing violin. It helps you wake up from a deep sleep by slowly lifting you out of REM, then Deep, then Light, then awake. It may take a few days or even weeks, but it should help your waking up. Also, looking at your symptoms, I would suggest looking in to whether you might be suffering from hypoglycaemia, or diabetes. This isn’t a diagnosis, but it seems similar to what I’ve heard symptoms can be. Hope you get better soon, and please keep us updated on your progress.
“The world is as bad as you think” - The Dollars