Tingling, muscle pains, dizziness 5 yrs

[SSLEE]

I am 37 years old and had always been in good health. My symptoms started about 5 years ago with numbing and tingling down my left arm. Then about 1 1/2 years ago I started to have dizziness and numbing sensations up the back of my neck, head and face. The dizziness was so bad I ended up in the ER. I also became dizzy and vomited when standing for a long period of time.  These kind of episodes would last about 5 days. I'd also have a lot of hip pain, ringing of the ears and TMJ. Then I became pregnant and didn't experience any of it. Since the birth, 6 months ago, the symptoms have returned. But I also now have pains in joints and muscles throughout my body. I noticed my neck really hurts along with my lower back. I now have tingling in the middle of my back. Recently I started to experience nausea. I can't stand for extended periods without feeling sick. I had an MRI of the brain and it was fine. I have seen a GI specialist (I have IBS so I thought it could be related), neurologist, cardiologist. Nobody has found the answer. Could these symptoms be stemming from the spine? Any input would be much appreciated. I just don't know which type of doctor to see next.