Baby is showing preference for bottles now…

My 2 week old has been showing a preference for bottles lately and when I try to breast-feed him he just spits it out and cries. Another thing that I’m struggling with is in the hospital the nurses suggested I used a nipple shield and I wasn’t quite sure when to stop using that so now he also won’t breast-feed unless I’m using a nipple shield. Does anyone have any suggestions as to how to wean off of the nipple shield and how to encourage my baby to like breast feeding again?