Basically for a while now I've been having a lot of difficulties with my physical health. The issues have been ongoing for at least a year or two by now and I am supposed to go to the hospital about it in a few months. It affects my whole body, I have difficulties with walking and sometimes my hands and sometimes I'll randomly get pain or numbness that even pain killers don't even help with. My parents know about all this but they don't seem to believe it's anything major.
So far I've been coping but the problem is I'm applying to university and I'm trying to get suitable accommodation because of my issues with walking and stairs. The thing is, my universities are asking for a letter from a professional that state my condition, how it affects me, and what accommodation requirements I need. All I have are the referral letters sent to the hospital, I don't have a diagnosis (who knows when I'll ever get one) and I can't get a GP appointment since my parents don't seem to care. Any advice is appreciated, I just want to get this accommodation thing sorted and once I'm at university I'll have more control to take care of my own health.