I'm really, really sorry that you're going through this. It must be absolutely terrible.
I don't think you'll get where you want to be with the post the way it is. I suggest starting a GoFundMe or Kickstarter page rather than linking to your personal PayPal account. It will make you seem more credible and people will know how much others have donated. On that note, you need to add more detail for people to be comfortable donating. What exactly is the money going for? If you want to try a drug, what drug? How are you going to get it? Do you have to fly to another country? How much is it going to cost and what is the breakdown of all of the expenses? You need to know what, very specifically, you are doing with the money.
I know this is really upsetting, and I feel bad asking, but did any of your doctors give you a time frame? I suggest noting that. ALS diagnosed in younger people has a tendency to progress more slowly, I think. If you could still live years, you might think about putting cryonics on hold for now. People are much more likely to fund treatment, and treatment is honestly your best bet. Please don't put your life completely on hold for ALS. You could still live years, and a very full life, even without a miracle drug.
I think it would be better if you shortened the beginning of your post quite a bit. I know you later say you got a diagnosis, but the first part of the story sheds a lot of doubt on your part. People tend to listen to medical professionals, and while I'm sure it was incredibly frustrating for them not to take you seriously, it doesn't add to, again, your credibility. Make the introduction short and then go into the diagnosis and after the diagnosis. Like I said before, adding details about the diagnosis and what you plan to do now would be helpful.
This is a really rough time, and because you have struggled with mental health in the past, I hope you are seeing a psychologist who can help you with this and putting things in perspective. If you aren't, I think this could be beneficial to you. Also, like you said, stress is unhealthy. I really hope you are taking the time to enjoy the time that you have.
One final note: I suggest editing or deleting your comment "I think it is one thing to accept death as natural after a long fulfilled life or if you’re snatched from life at a young age." This really undermines the experiences of others and is quite off-putting to me, mostly the second part. In that circumstance, there isn't even a little bit of preparation and there is no chance to say goodbye. It isn't easy to accept, either.
These are all just my impressions, so please take and leave what you want to. Good Luck, wishing you the best.