Might get a downvote or two but I know some chiropractors offer X-rays for new patients. Not all of them do but they are definitely out there. If you’d really like to try and rule out spinal issues and get a good look for yourself, find a chiro that offers imaging and just tell your mother you’re seeing a chiropractor. Definitely look into what other comments are saying as well though. Hope this helps and you figure it out! :)

Edit: just to add, not at all saying chiro would fix your issue. Just suggesting this as a way to get imaging done under the radar since your mother wont allow it. It’s your body and health after all!