Thanks for query,
Passing plenty of red blood cells in urine are common in urinary infection or due to kidney stones.
But passing free hemoglobin
called haemoglobinurea is not common and if it is there then it should be evaluated.
Common conditions where haemoglobinurea is found are,
Sickle cell anemia
,Thrombotic thrombocytic purpura,Malaria.
So consult physician and get investigated.
Ok and bye.