Undiagnosed chronic pain

Desperate and very tired of going to doctor after doctor. Any suggestions would be great. I will try to keep my list of health issues short. I have also had issues with iron (have had infusions), so that may be the cause of some of this. My current doctor does not believe it to be MS, she was right about my iron needs so I'm inclined to trust her. I've always had general pain (since middle school) but the last two years this has started to increase with back pain. Before it was foot pain doctors attributed to flat feet.

Here’s the laundry list:

Intense lower back pain (worse when standing/walking, I use a cane and sometimes a wheelchair), has flare ups for days that are worse. Fatigue Double vision Foot/ankle pain (i do also have flat feet though) Shortness of breath Palpitations (previous attributed to anxiety) Very occasional spasms (I thought it was just being cold, but my body kinda jerks or shivers a lot then stops)

Related info: 20Ftm, 5'3", 250lbs, black, in the US, has MDD, GAD, ADHD, Thalassemia