What is the reason for the low red blood cell count and the high proportion of reticulocytes?

Can't say & resupply: Low red cell count is either from lack of production, early destruction, or loss (= bleeding). That part of question depends on your Dr's eval and testing. Reticulocytes are young (/"immature") red blood cells. When RBCs are needed, production in bone marrow ramps up and cells are released a little early, which can tell on CBC.