What does elevated wbc and platelets means?

Many things: Elevated WBC can be due to many different reasons as can the increase in platelets. I recommend that you see a hematologist so that the abnormalities can be evaluated, worked-up and a diagnosis determined.

Many different thing: Depending on how high they are and what is the WBC differentials- it could be many different things- from reaction to bacterial infection, inflammation, bleeding process to primary bone marrow problem- like myeloproliferative neoplasm to even malignancy- either solid or blood malignancy. You need to f/u with your doctor.