Talk to Cardiologist on Shortness Of Breath N Palpitation

what could b a possible reason for shortness of breath n fast heart beat only exertion like climbing stairs, more physical activity , etc., the patient is hypothyroid since 2013 takes thyronorm 75, takes 5mg rovista , and had diagnosed 3 years back with h.pylori that eradicated 3rd attempt after that rechecked antigen test twice came negative. her CBC , iron profile , thyroid profile , lipid profile , magnesium , B12 , cortisol , estradiol ,electrolytes , abdominal usg ,ecg , echo ,NT-ProBNP all tests are normal / healthy normal. only Ferritin came 28.4 ( last month 23.2) . Iron 149, TiBC 327, Satur transfer 45.57 , HB 13.6 , RBC 4.33 , WBC 5.1 , Platelets 237 whereas, folic acid 3.91..she will be starting well women multivitamins.