Hi Daycia, it can be hard putting things like that into words that truly express just how bad things really are for you...........and if people haven't really felt it, it can be hard for them to understand. It might help some of them (and you in your appointments!!) if you reflect and write down exactly how you feel and some of the thoughts that go through your head when you're trying to push your limits and when you're having a panic attack.
And include in that the physical symptoms e.g. finding it hard to breath, feeling light headed/faint/like you're about to collapse; how it feels physically e.g. like having a massive weight on your chest (?), feeling physically sick and the thoughts..........
Or it might help if someone is there with you when you're doing something you have real problems with, and you can talk them though, step by step, as you're going along how it's making you feel.......then they might get a better idea of how it really is "close up"??
Then maybe there's some youtube clips that resonate with you that you can show them??
And ask them for some specific help/to work with you on improving things......that way they have some responsibility in it all too and they know that it is something you're trying to manage.
You could also show them some of the research you've done or for some of them.......even get them to help you do some of the research.......it might "open their eyes a little" when they're looking a bit more into it themselves.
Some people might always find it difficult to understand though........so try to make sure you're talking to and getting support from the one's who do, hey??
Alison