Hello I am currently 18 years old and I have been experiencing pain that has become common to me for years now that doctors won't help me with.

I was hit by a car going roughly 60-70 ks when I was 16 months old, the force of the stop is what hit me with the bumper of the car. I hit the ground and slid into the gutter as a result of the impact.
I didn't stay over night in hospital but I had a open wound on the right side of my head which wasnt cared for properly in result has lead to a deep indent on right side of head which is close to the temple.
My jaw has grinded out which has taken over 7 years to do so and my jaw dislocates on right side and clicks on left.
I have had severe headaches for a long time. A few years ago they lasted for 12-16 months and then stopped. But have started only just recently again, ringing sensations have also been at all times. This time they usually occur when I try to sleep which ranges from quiet to really loud ringing so my sleeping issues are worsened with this.
I have always had back pain, starts in lower to middle of back when doing activities like standing to long, cooking, cleaning etc. leaning over for too long, which causes a severe burning sensation that runs down to my knees, prominent feeling is down right side though.
Being a good student my memory has now effected me with the fact I'm having bad trouble remembering simple things that should be easy like spelling, maths. childhood memories, even stuff from last year have become hard to remember.
I never used to stutter but now sentences are getting harder to put together and repeating words happen a lot more frequently.
Insomnia runs through mums side of the family so I have trouble shutting my mind off at night sort of thing, but my sleeping issues started early teens as as much sleep as I was getting it wasn't enough. I would get ready to go out sit on my bed and pass out. And now no matter how tired I am I cannot fall asleep without staying up and doing something for hours or taking a muscle relaxant.
I've even had swelling and pain in my temples left one didn't really swell much or cause pain but the right one was bad.
I've had a hip xray, back xray and nothing are actually wrong with my bones. my back only had a sliding disc which I was told caused no pain.

the doctors I have seen palm me off as im all okay and I have no idea why, I have explained the exact same thing I am now and yet nothing is done about it. I honestly don't know how much pain I have to be in for something to be done or answers to be given. I just need help to know if I'm okay or not, if this is normal or not since damage to the brain in anyway should be looked at/concerned in the fact long term effect could be possible in the situation.

I would really love to hear back from you about any information and opinions you have.