Someone just told me i had blood in my eye. small circle , should i be concerned ? no one hit me there or anything

Hemorrhage: With no symptoms and no history of eye trauma, the most likely possibility is a subconjunctival hemorrhage - a slight leak of blood from a weak walled vein under the conjunctiva. These can be from coughing, straining, rubbing the eye, or simply an unknown cause. It will rapidly fade and cause no harm. If the vision is fine and there is no pain you can wait a week or so for it to fade.