23 years old. i have o negative blood. i have noticed unexplained bruising on my arms , it disappears then i have notice major bruising on calf muscle?

Unexplained Bruising: Any bleeding disorder you or your family member? Need to check out that as well as platlet counts.

Unexplained bruises: Unexplained bleeding as bruises, nosebleeds, blood in the stool, bleeding gums can all be signs of a clotting problem from an underlying disease. This should be evaluated asap with an examination and the appropriate blood tests.

Abnormal bruising: I don't believe this has anything to do with your blood type. Small bruises are common and usually don't indicate a problem. Large bruises (say tennis-ball width or larger) without trauma often indicate a clotting problem. The only way to know for sure is to see a healthcare provider and get some blood tests.