Could I have permanently damaged my back? I was playing soccer and as I slid for a pass I jarred my back it hasent been right for 2 weeks, my parents say its just muscle problems but I am seriously worried about my lower spine

Most. Most back injuries heal up over a period of weeks to months. I would recommend assessment by your primary care doctor to rule out serious injury like spinal fracture. If no broken bones are found then the initial treatment includes rest and anti-inflammatory medications (ibuprofen, Naproxen or Celebrex (celecoxib) unless you are unable for medical reason such as ulcers, kidney disease, etc) followed by physical therapy or chiropractic therapy. Patient who fail physical therapy may be a candidate for spinal injections. Most people will improve over time and not require surgery.