What Causes Shortness Of Breath And Heart Pounding, Abnormal Blood Results Showing Low Ferritin And Iron?

This is my blood test results, I have had an upper GI and a Capsule Endoscopy, which all came back normal. My last Colonoscopy 2 years ago was normal. I had a partial nephrectomy because of kidney cancer in 2019. I am still out of breath with exertion and my heart pounds somewhat. I go back for more blood work in May. !st test CBC (INCLUDES DIFF/PLT) Analyte Value WHITE BLOOD CELL COUNT 6.9 Reference Range: 3.8-10.8 Thousand/uL RED BLOOD CELL COUNT 5.02 Reference Range: 3.80-5.10 Million/uL HEMOGLOBIN 12.1 Reference Range: 11.7-15.5 g/dL HEMATOCRIT 38.4 Reference Range: 35.0-45.0 % MCV 76.5 L Reference Range: 80.0-100.0 fL MCH 24.1 L Reference Range: 27.0-33.0 pg MCHC 31.5 L Reference Range: 32.0-36.0 g/dL RDW 15.8 H Reference Range: 11.0-15.0 % PLATELET COUNT 312 Reference Range: 140-400 Thousand/uL MPV 11.5 Reference Range: 7.5-12.5 fL ABSOLUTE NEUTROPHILS 4347 Reference Range: 1500-7800 cells/uL ABSOLUTE LYMPHOCYTES 2111 Reference Range: 850-3900 cells/uL ABSOLUTE MONOCYTES 269 Reference Range: 200-950 cells/uL ABSOLUTE EOSINOPHILS 110 Reference Range: 15-500 cells/uL ABSOLUTE BASOPHILS 62 Reference Range: 0-200 cells/uL NEUTROPHILS 63 % LYMPHOCYTES 30.6 % MONOCYTES 3.9 % EOSINOPHILS 1.6 % BASOPHILS 0.9 % IRON AND TOTAL IRON BINDING CAPACITY Analyte Value IRON, TOTAL 37 L Reference Range: 45-160 mcg/dL IRON BINDING CAPACITY 502 H Reference Range: 250-450 mcg/dL (calc) % SATURATION 7 L Reference Range: 16-45 % (calc) FERRITIN Analyte Value FERRITIN 8 L Reference Range: 16-288 ng/mL. 2nd test just done in February shows current and previous test results. Iron and TIBC Test Current Result and Flag Previous Result and Date Units Reference Interval Iron Bind.Cap.(TIBC) 486 High 477 09/07/2018 ug/dL 250-450 UIBC01 416 High 382 09/07/2018 ug/dL 118-369 Iron01 70 95 09/07/2018 ug/dL 27-139 Iron Saturation 14 Low 20 09/07/2018 % 15-55 Ferritin Test Current Result and Flag Previous Result and Date Units Reference Interval Ferritin01 15 28 09/07/2018 ng/mL 15-150