breastfeeding

So please tell me if I'm doing this right ... kinda new to it 
So I switch between boobs each feeding . I do my left and right for 1 feeding. So when I feed is it right ckf me to switch and use the breast that didn't get as much time spent on it . 
Example: my boy spent 12 mins on my left and 10 on my right.. so now I'm giving him my right boob first this feeding 
It honestly seems to be more complicating to do it like this 
I much rather use ONE boob only for 1 feeding ...what should I do???