I Have Two Medications That Both Say Take One By

I have two medications that both say take one by oral route 2 times a day for 14 daya and the pharmacist told me to take one of them then take the other one an hour later then repeat that one more time. So I would be taking 4 pills a day. But my mom thinks that isn't right and believes that would be overdosing because one of the medications is 500MG and the other is 100MG.
I'm just confused on what to exactly do. Can you help me?