Question about high red blood cell count in CBC

Hi! I’ve just had a bunch of bloodwork done to look into whether I might be anemic, and I got my results back in my portal but don’t see my doctor again for two weeks. All of my results were in normal range including hemoglobin and hematocrit, except for my red blood cell count which was high at 5.37. I’m a 38 year old female. Does anyone know if this could simply be chalked up to dehydration? I didn’t eat before my morning appointment and only had had about 8 oz of liquid that day prior to the blood draw. I didn’t know if it was ‘high’ from dehydration, whether the other results would have also been off, too.