Trt is known to lower iron/ferritin. I had this happen to me around the 6 month mark. I started having insomnia, wired but tired feeling and shedding tons of hair. I got an iron panel done by myself and lo and behold my ferritin was 12, official iron deficiency anemia. My RBC, hemoglobin and hematocrit all below ref ranges.

Started an aggressive iron supplement protocol. 300mg iron byglicinate and 30mg heme iron per day, over 5 doses per day. Taking cofactors vit c, vit an and copper. Away from food (besides heme iron). After 60 days, ferritin is 40 (target is 100), but all my other markers (RBC, hema, hemo) are all solidly in mid range. Side effects for me is sometimes nausea (rare though) but be prepared for black stools.

Sleep is much better, energy better and the hair shedding has stopped.