You do not have enough traffic to know if you are doing Facebook ads right or not. It can easily take a 100 add to cart / initiated checkout before you get a sale. You need to continue to test your Facebook ad copy and creative images to see what is going to work.
Also, you are in a super competitive niche selling watches, which is not something people buy often. Your store needs to reflect the higher expectations that customers have. Your store still has some of the features people suggested you get rid of based on your last two Feedback On My Store requests:
Unless you change those areas, there is no way you can expect to compete in this niche as the changes are reflective of your store meeting the bare minimum expectations that people have when they buy anything, let alone watches, online.