Ever have one of these?

A subconjunctival haemorrhage occurs when a small blood vessel under the conjunctiva breaks and bleeds. The blood is trapped under the clear conjunctiva – like a bruise. This condition is painless and, although it can look frightening, is harmless.
Causes of a subconjunctival haemorrhage include coughing or sneezing, although many occur spontaneously. Recurrent haemorrhages may be caused by high blood pressure or diabetes. The haemorrhage does not require treatment and usually absorbs of its own accord. A red eye associated with pain or a reduction in vision may be more serious and requires more prompt assessment.