If I have already submitted my self employed income on T4A, am I double reporting when I add it to self employed professional fee?

If you have entered a T4A with Self-Employment income it, then TurboTax will automatically create a business for you with that amount included in the Self-Employment section. 

To see it in TurboTax Online, click on Find (magnifying glass) in the top right-hand corner. Type "self" in the box, then select "Self-Employment Summary" from the list and click “Go”. It should be listed with the T4A amount as the Net Income.