Persistent resting heart rate >100/min with marked fatigue and restlessness needs evaluation.
Possible causes include anemia,
thyroid disorder, dehydration, infection, anxiety/stress or an arrhythmia.
Please check BP, SpO₂, temperature and resting pulse properly.
Get a 12-lead ECG to determine the rhythm.
Initial tests: CBC,
TSH/FT4,
electrolytes, renal function and blood glucose.
Next Steps
Avoid excess caffeine, nicotine, energy drinks and other stimulants meanwhile.
If HR remains >120–130 at rest, or there is chest pain, fainting, severe breathlessness or dizziness, seek urgent medical evaluation.