Advocating for Myself with Chronic Pain

(I don’t have either of these conditions but the app grouped me with it because I put joint pain) Currently a sophomore in high school and I missed over a week plus today because of how debilitating my pain is. It’s frustrating that unless I’m at that point my parents don’t see how painful it is. I currently use a cane, but recently pain has been spreading to my wrists because of my hips relying on my cane for stability instead of just being able to stand. I’ve been thinking about possibly getting forearm crutches or even better, a wheelchair, though my parents constantly tell me “I don’t need one” or that “Only people with [condition] need that” or even that I just need to do physical therapy exercises. It’s super frustrating and difficult to advocate for myself, doctors especially, since my parents (despite being the ones that dealt with my conditions and surgeries when I was younger) have a more valued opinion than me. At least it seems like that