Is it normal to be nineteen with a bad hip

When I was fourteen I was diagnosed as having loose joints in my hands, which did not cause pain. At fifteen I developed shin splints, and my knees started hurting at sixteen. Now I'm nineteen and my hips hurt whenever I bend to sit down, and they pop out of place momentarily when I stand up. I play roller derby, and after practice it is impossible to move my hip without pain and sleep is a nightmare unless I stay completely still. I often end up limping without noticing and my pain is getting worse. As a nineteen year old, is this common or normal to any degree?