Brief Answer:
This is called subconjunctival hemorrhage

Detailed Answer:
hey thanks for your question. If it is indeed blood then it is called sub conjunctival hemorrhage dear and it can be due to many reasons . Yes hypertension is one of them but besides that also we have others like cough , constipation , minor trauma . It will resolve in two to three weeks of its own dear . If your eye feels heavy you may use lubricant eye drops three to four times a day .Besides that if it is recurrent then we may need to do some blood tests like bleeding and clotting time . Hope my answer helps you . If you have any follow up queries i would love to answer the same . Regards

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