Re: Pees a lot and other question
A baby can't pee too much.
4 weeks is a little early for a baby to space out his poops to every other day, but since he is gaining well I wouldn't worry.
Nursing on one side at a time is something you want to do only if you have an oversupply of milk or if the baby doesn't seem to want the second side. As long as the baby's poops are yellow, you should allow the baby to finish the first breast at his own pace and then offer the second breast. (Yellow poops indicate adequate hindmilk intake.)
At just 4 weeks, I would continue to wake your baby every 2 hours during the day. I would probably allow a 4-5 hour stretch at night because he is gaining weight nicely. But if you want to be ultraconservative, waking him every 3-4 hours at night won't hurt.
Coolest thing my big girl said recently: "How can you tell the world is moving when you are standing on it?"
Coolest thing my little girl sang recently: "I love dat one-two pupples!"