OP, your situation isn't that unusual. I was a little bit slower than you in the 400 and a little bit faster in the 1600 in high school. In college, I got down to 4:37 for 1500 and 17:25 for 5k. That took four years of hard work on top of the four year of hard work in high school. In graduate school, I became a coach and helped a lot of people make huge jumps from high school to college. Much larger jumps than I made myself. One guy went from 10:10 for 3200, having run for York high school, to 14:19 for 5k. But others made smaller improvements. Everyone is different. Some are late bloomers. Some, like me, never really bloom at all (perhaps I am just an extremely late bloomer? I'm still trying to find out).
You can get a lot out of this sport whether or not your are a scoring runner. As long as you work hard and bring an attitude to practice that helps your team's scoring runners want to work hard, then you are an asset to any team and any coach. And don't worry too much about what your potential is. In my first several years of running, I wasted many racing opportunities because I was too concerned about what I couldn't do and not focused on what I could realistically do. Reaching your potential, no matter how modest, is worth your time and effort. You should never be ashamed of it.
Also, see a physical therapist about your hip. If there is a physical limit preventing you from training harder, then go seek out the knowledge that you need to overcome that limit. If you can't run faster because you don't have the talent, that's fine and it's honorable to do the best that you can. But don't let yourself be hampered by a lack of knowledge.