Hello dear.
This could happen because of several reasons. Below are the common ones:
1. Sitting in same posture for prolonged periods of time.
2. Looking at a screen/monitor for a long time.
3. Standing up abruptly.
4. Low blood pressure (especially during periods)
5. Mild anaemia
6. Refractive errors (you need glasses).
Next Steps
A few tests will be necessary for confirming the reason for your symptoms.
Health Tips
Please consult.
Answered2018-08-27 16:49:06
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