Blood in eye, also known as subconjunctival hemorrhage,
can be due to many reasons, some trivial, others potentially serious
Spontaneous subconjunctival hemorrhage can be the result of ...
Coughing, sneezing, excessive straining,
rubbing eyes, foreign body like contact lens, and pink eye (eye flu)
Rarely a medical disorder (bleeding disorder), severe hypertension, and drugs like aspirin or head trauma can cause the same,
I would recommend that you see a doctor, get your BP checked, and watch for any other symptoms/ a worsening bleed.
You may put some OTC eye drops like GENTEAL, REFRESH TEARS etc. if the bleeding causes some irritation,
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