I suffered a fall about a month and a half ago. I didn't think I'd need assistance but the injury is persisting when I wait in lines (as I'm unable to sit and I need to keep my knees bent as much as possible) is there any way I can receive ADA accommodations even tho the convention has started?
Yes. ADA laws do not require that disabilities be permanent in order to be accommodated. Organizations aren't even allowed to ask what disabilities a person has, only what accommodations are needed.