rest assured that all this is very normal. its normal for a baby to choose a side it likes better and will want to nurse more from that side and therefore that side will produce more as the baby nurses better from the side it likes more... you will notice the change in breast size most likely the first couple months and then as your milk supply is established, they will even out more and not have that all the time feeling full feeling... All the changes you said to me sound very normal as your breasts adjust to your milk supply. it just means baby is doing well and able to nurse effectively to establish your milk supply perfectly :)

I hope that helps! Good job on exclusively nursing!