Hello
Welcome to health care magic.
Dizziness,fatigue,discomfort behind chest since 1 day may be because of gastritis/
dehydration caused due to exercising.
If I were your treating doctor,I would recommend,
-PPIs like
omeprazole once in morning for 3-5 days for gastric symptoms.
-Keep yourself well hydrated during and after exercising.
Have minimum of 8-10 glasses of water a day.Fluid with electrolytes preferrable to cover up the dehydration.
-Have some gap between two sets of exercises to let body cool down.
-Have regular
multivitamin and calcium supplementation with balanced healthy diet.
If the symptoms persists,consult physician for blood tests like blood
haemoglobin,blood glucose,
blood lipids,ECG to rule out age related medical conditions.
Hope this information helps.
Feel free to ask any more doubts.
Wish you good health.