My Apple Watch is only saying "You have a new message"... it's like it's making fun of me because it knows I then wonder what it's all about

This maybe a privacy setting you have on where your watch will only let you know that you have a new message. Once you unlock your iPhone you should be able to see the full email message with the name of the sender. use this photo below as reference and it can help see by a preview of the email you maybe getting from a

sender.