I am 23 yrs old and in ALOT of pain. Can anyone help me?

I was thrown from a vehicle traveling 75 mph at age 15. I was at a dead sit still and hit from behind by a truck traveling 80 mph at age 19. Just the 2 major accidents I have been in. I have bad aching neck and back problems since the accident in Dec. 2004. I went to a few different doctors and they insist that nothing is wrong. They did MRIs, CTs, X-rays, and some die thing all in 2004 and 2005. I have went to physical therapy and a chiropractor    I am still in PAIN it comes and goes but anytime I am active in the least little bit I hurt. A few months ago I was in a little rear ended accident and had been very sore. The soreness went a way after a few weeks as normal. But I few weeks ago I cleaned out my garage and have not been able to look down with out SHARP pain shooting down to my mid back. I decided to go back to the doc. (a different doctor).  He did a MRI and CT scan. He told me I had scoliosis and gave me a few pain meds. I am out of pain meds now and back into pain. I can hear a cracking or sizzling (sounds like pop-rocks stuck back there) noise in my neck when I turn from side to side. My question is If the doctor is right I do have scoliosis how come they didn't find it 8 years ago with they did test in my first accident. I am still in pain. The doctor started me off on Loratab 10 and flexerial 10, then Tramadol 50 mg and trizadine, and now darvocet-n and soma 350mg  the only thing that worked was the Loratab and flexerial. I asked him for those again and he does not want me to get addicted to them. I don't see how I can, if I only take them until he finds out what is wrong with me. My Question is should I continue to go to him? How did they just find out I have scoliosis after 23yrs? Why am I still in pain after 8 years? Is there other help out there? I am only 23 yrs old.