I never checked ferritin either until a year ago when I developed a benign (but annoying and distressing) cardiac arrhythmia.
At that time, it was 11 (30-400). Now, a year later, the arrhythmia has returned and when I checked it, ferritin is low again. I know it was at least in range (40) in the interim.
Blood banks really should be checking ferritin for their super-donors, but it isn't in their interest to find costly non-FDA mandated reasons to disqualify their best donors. Also, to be fair, high HCT and low ferritin don't normally go together outside of the distorted blood profile that can result from exogenous testosterone administration.
BTW props to Apollon for putting ferritin on my radar.