If my blood test shows left shift of neutrophils, which i understand may be related to fighting infection, would not the overall number of neutrophils and therefore wbc also show increased number? thanks?

The white cell count could be within normal range but it can still be relatively high depending on your baseline number. Give example: if you normal white cell count is 6K and it is now 10K which is still in normal limit but in fact it increases 66% so if the neutrophils percentage is 90% it can be a true left shift even the total neutrophil count may be still within normal limit.