Pumping question

Ive been slowly introducing a bottle to my 7 week old. So far I've just been using the Haaka to collect milk and give her an ounce before i nurse. I know i need to work up to getting her to take a full feed. I don't go back to work till she'll be 5 months. Here's the question: usually she feeds on just one side per feeding. Would i pump just one side to match the bottle she is eating? Does it matter if its the same side each time or do i need to alternate? Does it matter if it's the same time each day?