What does it mean to be followed by a raven in your dreams repeatly?

Like crows, ravens are carrion birds and scavangers, so they tend to be associated with death in Western Culture. In other cultures, including the Native American mythologies, ravens are regarded as messengers. So the actual meaning of these dreams depends on the dreamer and his/her own culture and traditions. Very generally, the dreams might suggest that there is refuse or left-over trash in the dreamers life that needs to be "scavanged" or cleared away.