Ferritin levels and taking Iron supplements?

I have been losing a lot of hair over the past few months. At the same time, I developed a weird rash, which was treated successfully by a derm. Dr. after many natural remedies on my own. Also, had a lot of creaking in the neck and knees! I love to exercise, so this was driving me nuts with the sounds! I have done many Colon Cleanses and a Humaworm parasite cleanse. Haven't done a liver cleanse, but have taken various liver supplements. I also think I have Candida.

Blood levels: ferritin=56, TSH=2.5, Vitamin D=31 (all kinda borderline, but not terrible)

Here's the strange thing! I started taking thyroid and iron supplements. The Derm. Dr. told me not to take as much iron, so I cut the dose in half, then didn't take it. My hair loss, which had subsided a lot, started again! (same with peeling lips!) So, I'm back on the iron yesterday - I think what I have read about ferritin needing to be over 70 is very accurate. I believe I'm still low.

Vitamin D, I believe, has helped the extra joint noise decline!

I now believe that these borderline blood levels can still show lots of symptoms! I'll have to go with what reactions I'm getting, and not just necessarily listen to the Dr.

Anybody else out there with symptoms, but only borderline blood levels? I wonder what causes this result?