No support from family

I’ve been dealing with joint pain since I was 12 and I’m now 19. I’ve seen multiple doctors and had tests done around when I was 13 or 14 but everything came up negative. I was sent to a rheumatologist but my parents told me I could only see him once so of course nothing came out of that. I kind of have episodes were I’m hurting and times where I’m not and I’m currently having another “episode”. I told my parents because I wanted to go back and see someone for it and I did and was told again that they think it’s autoimmune and I’m currently waiting for the rheumatologist to call me back so I can set up an appointment. My parents however tell me constantly that it’s just my mind and that I’m making things worse than they actually are. My brothers say the same and they also say that I just want something to be wrong with me. This is also a huge part of why I just dealt with the pains I get and didn’t go to the doctor. My joints and muscles don’t just hurt because I don’t exercise, I don’t experience cold urticaria for no reason, and I don’t have trouble staying awake at work because I don’t go to sleep at an appropriate time. I hate being told that the problems are things I made up in my head or that I’m making a bigger deal. It sucks and I don’t know how to get that point across to them.