Signs of heatstroke are very high temperature (more than 104 F), some confusion or personality changes, even a coma, and the skin may be hot and dry. Other signs
include a fast beating heart
, fast breathing, blood pressure abnormalities, lack of sweating despite a high temperature, changes in consciousness, dizziness/light-headedness, headache and nausea, and fainting.
As you can see, headache, nausea, and vomiting are signs of heatstroke.