I was recently told by my Dr that my anemia is a level 9 and put on a iron supplement?

I was recently told by my Dr that my anemia is a level 9 and put on a iron supplement. Within a few days, the shortness of breath, fatigue etc has dissipated significantly. Could it just be an iron deficiency or should I be more worried? The information on the internet has me completely terrified and worried.

Age: 46
Female
Medications: Ferrous Sulfate, B12, fish oil and a multi vitamin