i saw your question . its very simple take one Xray for your spine report will tell what and where spinal curve changes in angle , at this age because of muscular imbalance your posture will change if u do some exercises you can correct your posture
dont use braces, lumbar belts and other stuff these will worse your problem all these external supports will make muscles weak so try to avoid and if you tell X ray
report i can guide you for perfect treatment .
my mail id firstname.lastname@example.org