Im having really bad back pains after giving birth 6 months ago, anybody know what this could be?

I am 23 years old and have 2 children. After my first pregnancy my back pains began on my lower back. They never went away, from morning to night they remained persistant, without any relief. It got to the point where between activities I would have to go lay down and put my legs up on a pillow to get some relief to be able to get thru the rest of my day. I finally decided to go to chiropractor and he had some xrays done, he claimed my "pelvis was still rotated from my previous pregnant position." However I repepated this claim to my gynocologist and he laughed saying it was crap. I then became pregnant with my second child. During this pregnancy, my back pain was unbearable. It went on from being simply my lower back (which is normal durin pregnancies I know) to extending to my entire left side of my back, neck and left leg. I was diagnosed with sciatica during my pregnancy. Its now been 6 months since my baby was born and my pain is horrible! It never goes away. From the minute I open my eyes to the minute I close them my back is in pain. The pain is in my lower back, under my left shoulder blade, and neck. Its the strongest under my shoulder blade. If I sit a certain way, my entire left side goes numb. Sometimes I feel a tingly feeling under my shoulder blade like if a liquid is being released(I'm not saying that's what's going on, just that that's how it feels). If somebody out there knows what this could be please explain.. I'm guessing it could just be my sciatic nerve but I'm afraid it may be something more serious. If it is my sciatic nerve, what can/is usually done for this? Should I go to the chiropractor or orthopedic? Thanks so much in advance and I apologize for the endless story.. :)