My DS is 11 weeks old. He's a good feeder but ...

My DS is 11 weeks old. He's a good feeder but has developed a preference for one side over the other. I start him on his least favourite side and he will usually only suck for a few minutes and then pull off and cry. I try to put him back on but in the end i usually give up on that side. When I swap him to the other side he sucks happily for about 20 minutes and is happy and satisfied. I had an infection in his least prefered side a few weeks ago and was wondering whether it has affected my production or flow on that side only? Has anyone else experienced this?