Welcome to HealthcareMagic forum.
Blood pressure readings are not standardized to all individuals. Some individuals can have below par blood pressure readings and remain asymptomatic.
However in your case, though you normally would have a low BP
, presence of symptoms is concerning. Perhaps you were dehydrated after the massive work out and blood pressures dropped or you could have an underlying heart ailment.
Things need to be sorted by a detailed clinical examination and laboratory tests. I suggest you to consult your physician / cardiologist as soon as possible.
In the mean time drink enough fluids and avoid strenuous physical activities.
Hope this helps.
I wish you a speedy recovery