The low iron may be causing the headaches. From lab corp:

"Without adequate iron stores, the body cannot build the hemoglobin molecules needed for red blood cells to function.
Headaches are another frequent complaint with anemia. When your brain doesn't get enough oxygen from the blood, it can trigger headaches. The headaches may be dull and constant or come and go"
https://www.ondemand.labcorp.com/blog/anemia-symptoms-what-your-body-might-be-telling-you#:~:text=When%20your%20brain%20doesn't,of%20breath%20easily%20with%20anemia.
You may want to make an appointment with a rheumatologist. Hope you find help soon.