In some cultures in the Northern Hemisphere, the astronomical March equinox (varying between 19 and 21 March) is taken to mark the first day of spring, and the Northern solstice (around 21 June) is taken as the first day of summer. In other traditions, the equinox is taken as mid-spring.
Circulation problems that cause dizziness. You may feel dizzy, faint or off balance if your heart isn't pumping enough blood to your brain. Causes include: 1  Drop in blood pressure.
If your blood pressure drops during the test and you feel faint or dizzy, the test is positive. Your doctor may suggest changing your medicines or having more tests. If your fainting is due to a slow heart rate (bradycardia), your doctor may recommend a pacemaker.