Severe iron deficiency out of nowhere? Ferritin was 107 in April, now 0.1 in July

April 2025: Ferritin = 107 ng/mL - healthy July 2025: Ferritin = 0.1 ng/mL - severely deficient

I’m honestly confused and kind of worried. Back in April, I got a full set of labs done because I was experiencing really bad anxiety and wanted to check if there was anything going on physically. Everything came back normal, including my ferritin, which was at 107 ng/mL solidly healthy.

Fast forward to July, and I just got re-tested. My ferritin is now 0.1 ng/mL, and I’ve also developed hypothyroidism (my FT4 is very low). I have a doctor’s appointment coming up soon, but in the meantime, I’m trying to understand:

Is it even possible for ferritin to drop that fast from 107 to 0.1 in just about 2-3 months? I haven’t knowingly had any major blood loss and I’ve been having normal regular periods,I don’t think I’ve never had issues with iron before. This feels really sudden and strange.