Took a blood test which showws no abnormalities, so does this rule out leukemia?

Yes most likely: Leukemia, although it begins in the bone marrow, will soon affect the peripheral blood causing low hemoglobin(anemia), low platelets and low or high WBC count. All these changes can develop quite quickly( in 4-6 weeks) in case sof acute leukemia although chronic leukemias take several months to evlove enough to affect the peripheral blood.

Probably: Probably yes. There are rare instances of leukemia, especially in a very early stage, when no significant abnormalities may be present in the peripheral blood, but that is a very unusual situation.