A few months ago my legs started feeling super heavy without every feeling recovered, feeling tired all the time, having headaches, and super low all the time, even when running. Recently, it has felt like I can't get my heart rate high enough to get real workouts in. I realize that anemia normally increases heart rate, but I've heard of instances where it has caused heart rate to decrease. My tempo pace has dropped by 38 seconds in a week. A few weeks ago I went to a doctor who thought I was probably anemic, but she said my labs were fine. The labs themselves seem to suggest otherwise. I have an iron sat of 8%, a ferritin serum of 8ng/mL, an iron of 37 ug/dL, an MCH of 25.7 pg, MCV of 79 fL, mono of 0.8, monocyte % of 9.8, and RDW of 16.6%. The doctor said I might want to take iron supps anyway, and I've started doing that. The past couple of days I've started having random episodes of tingling in my arms and legs, light headedness, feeling like I'm not getting enough air in, hot flashes, and heart rate shooting up by about 75 when I'm not doing anything. I woke up last night struggling to breathe, and one of these events happened following that. My mom is a therapist and is convinced these episodes are panic attacks, but I've been told anemia attacks and panic attacks present similarly to panic attacks. Also, I've never had panic attacks prior to this. I've been trying to keep my training regimen the same, but I've had to take my moderate runs down to a pace that is under recovery pace to feel like I'm getting enough oxygen. I'm trying my best to complete my workouts, as I'm a college athlete, but it has become damn hard. I've even had to greatly reduce weight during lift sessions, which are generally extremely easy for me. I would like to see another doctor about this, but I doubt anyone will be able to get me in in the next 3 weeks before I go back to college. Anyway, my question is: How do you know when to take a break from running or reduce your mileage with anemia?