Brief Answer:
subconjunctival hemorrhage

Detailed Answer:
Hello and thank you for your question.
This is called a subconjuntival hemorrhage. They are common and sometimes occur after trauma but also occur frequently without any cause. They are benign and will resolve in a few weeks.
One thing that may help this resolve quicker are eye drops like Visine. This type of eye drop can constrict the blood vessels and make the redness less. You may not be able to use this type of drop if you have glaucoma so if you have condition, then check with your eye doctor first.
The other thing that can help this clear up is cool compresses to the eye. Just we a wash cloth with cool water and hold it over the closed eye. Do not put pressure on the eye.
If this is not cleared up in two weeks or if you develop pain or visual changes then see an eye doctor right away.
Regards,
Dr Robinson

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