Engorgement and sleepy baby!

Hi! My baby is 6 days old and eats pretty well but he is also a very good sleeper and even if I do everything to wake him up after 3 hours to help me relief my sore engorged breasts he usually takes longer to wake up and then he is full with only one side! To make matters worst he has a "favorite" side and he is pretty stubborn about it! I've pumped a little bit yesterday to relief the pressure and even had a quick warm bath. I also put cabbage leaves in the freezer... Anything else I should be doing? Tips on how to make him like his least favorite side?