constant nursing?

My son is a month old and he is breastfed and formula fed(no judging or opinions please, it works for us). When he takes a bottle of formula he is up to 4oz right now per feeding. I breastfeed him whenever he wants though and always offer my breast first and have had no issues with my supply. Lately though he wants to be nursing all the time. Even when I know he's not hungry. He just comfort nurses and will be wide awake nursing. Sometimes he will fall asleep but sometimes he is just up nursing. Is it normal for a baby to just want to nurse all the time? I find it hard to get things done because he just wants to comfort nurse. I've tried pacifiers and he doesn't like them!