You need finasteride (finasteride) ASAP, maybe dutasteride if your case is aggressive. Your temple hairs are miniaturized, not gone so that's good for recovery. And the fact that you're more or less already fully developed, have facial/body hair means that it's probably safe for you to take finasteride, even though you're under 18. I would say, go see a Hair transplant doctor, ask them to prescribe you finasteride, monitor your progress and good luck. If finasteride doesn't halt/reverse, try adding minoxidil or switching to dutasteride. Because of your age and temple recession, you likely have an aggressive case, do not waste any time, act yesterday, or failing that right now. With hair loss, like most things, an ounce of prevention is worth a pound of cure.
Ask a specialist/dermatologist or GP to prescribe you Proscar (5 mg finasteride tablets) cut them in to quarters and take one every day.