How to ask for help from doctors after a car accident?

[acatalanogm]

Hi,
I apologize for the long message but I just want to know how to get a doctor to listen to all of my problems instead of concentrating on one area only.  I was in a car accident 2 weeks ago. It was a head on collision. My car was totalled. I was wearing a seatbelt but my airbag did not deploy. I was hit head on but more to the drivers side (I was the driver). Approximate speed was 50 km for me and 50km for the other driver. Both vehicles are 4 door sedans.  The night of the accident, I had only neck pain and in my opinion, didn't need medical attention. I have a fairly strong threshold for pain. and there are far worse off people (potentially fatal) that require EMS. By the following day, I had back pain, neck pain and dizziness.  By the 3rd day, I had nausea and leg/hip pain.  By the 3rd day, I went to a walk in clinic. He advised pain killers, physio and bed rest.  My insurance is covering physio and I have been going 2-3 times per week.
My back and neck are not getting better. Neck cant be touched until I get xrays.  I went to another clinic and was told by the physician that he doesn't even touch car accidents and I need to see my own gp (which I explained was away on vacation from what I was told).  I told him I needed xrays just so I can get physio to touch my neck and help me.
I have thrown my back out 3 times in 2 weeks (only from getting from a lying position to standing or bending down to standing).  
I am also experiencing some chest pain (middle of my breast bone - forgive me, I am not good with anatomy), but I imagine this is from the seatbelt.
I finally went to emergency after 2 weeks.  I was admitted overnight to get xrays and a CT scan of my neck only. It came back with a filling defect in my straight sinus, arachnoid granuloma and a venous sinus thrombus.  Which may explain the dizziness, nausea and slight pressure in my head. Doctor said a mild concussion.

My question is, how do I get a doctor to do full body xrays and scans, exams, etc. for everything I am experiencing and not just the neck.  It seems like the doctors hear only one part of my complaint and concentrate on that rather than everything as a whole.
I just want to make sure everything is checked so I can get proper treatment and get better faster. I am 33 years old, healthy, athletic my whole life and now I can't even do a load of laundry or stand and sit for more than 5-10 minutes without pain.
  
Here are all of my most concerning symptoms:
neck feels stiff - cannot move it without cracking - both sides and back of neck - left side worse
back - upper, middle and lower but middle is the worst - cannot move it or twist it in any direction without pain
left thigh/hip - just feels really sore, almost as if I worked a muscle I haven't used before but I am athletic
left arm and shoulder - goes numb from time to time and back and shoulder hurt if I move it
breast bone/chest pain - at times difficult to cough, breathe, laugh
nausea/dizziness/slight pressure in head - just comes out of nowhere - but worse if I lay on stomach, turn, go from sitting to standing, etc.
There are other tiny little things but the above are the most concerning to me.

Any GP's out there that can tell me how to get a doctor to check my whole body? I don't want issues down the road. I want to try to fix all issues now so nothing happens later on or gets worse later on. Any advice will be greatly appreciated.