Getting a concussion at this stage of your life is going to be the hardest. Your already dealing with the pressures of being a teenager and having this thrown into the mix doesn't help. I know this because I got 3 successive concussions in 6 months when I was 16 and 2 more in the last 6 months.

Now at 22 I am still dealing with things very similar to what you are and have been for the last 6 years. Like you I was a straight A student and never worked for it but then i fell to a 70% avg student. I ended up having to take an extra year in high school since i couldnt earn all my credits to graduate in time and it was so embarrassing. I wasn't ready to give up and jumped into a full course load my first year of university. Since i pushed myself and just wanted to be like everyone else, i ended up overloading myself and dropping out. I dont regret that decision though because even though it was not the smartest thing, at least I can say I tried and that is when i found my boundries.

Parents/teachers/peers wont ever understand what your going through. If they havent experienced it themselves and can't see the problem, they think you can just get over it and they move on while your still in the same position which is frustrating. All you can do is keep repeating yourself to them and hope one day it sinks in. If you have some really close friends that dont understand and they are important to you, take them to a doctors appointment so they can hear it from a professional. That's when it will become real for them.

Sleep issues are the worst. If you cant sleep nothing gets better and only goes downhill. Most of recovery happens when you sleep, so its really important. I use 5mg Melatonin on nights when im kind of tired but when its past mid night and im still wide awake and need to get up for work at 7 the next morning i take 10mg. I get mine from a naturopath and it has worked better than any of the prescription meds ive gotten from a doctor and ive now been using it for 4 years. If you can id strongly suggest finding a therapist who deals with natural medicines. (always consult doctors before taking something new though just in case it can interact with anything else you may be taking)
Also, for the headaches, something really important is if your taking advil/tylenol a lot you should definetly cut down. your body will get used to it and it will stop working for you and then you have to go into perscription meds from there. I know head aches are really painful, they've become apart of my daily life, but there are other ways of reducing them. Find something that relaxes you entirely, it might not make the pain go away fully but the worst of it will go. I use a hot tub or warm bath or shower and im ok for the day.

The most important piece of advice i can give you is dont be too hard on yourself and never give up, things may take longer to achieve now but the end result is well worth it. If help is offered take it, Don't let pride or embarrassement get in the way of your recovery!

Good luck with everything!