What is the earliest time you can experience fatigue after conception?

Answer 1

Generally it is 4-8 weeks. But some mothers to be feel it earlier than that as little as 1 week.

Fatigue ranks high among early symptoms of pregnancy. During early pregnancy, levels of the hormone progesterone soar. In high enough doses, progesterone can put you to sleep. At the same time, lower blood sugar levels, lower blood pressure and increased blood production may team up to sap your energy

Answer 2

It takes between 6 to 12 days for a fertilized egg to travel to the uterus and attach itself, so I would say it would take about a week to two weeks before having symptoms like fatigue.