I agree that it would have been better to let him know BEFORE the wedding that you're poly (assuming you were aware at the time that you were poly... I know it kind of sneaks up on people sometimes
Other than that, I think just give your husband some time to process. Going from the mindset of finding your one true love and living monogamously happily ever after to having multiple loves and all the things that go with that is a hard thing to do! Especially when it isn't your feelings/desires that cause the shift. Let him process for a bit and then just talk to him about what it would mean for your relationship. You may find that he isn't open to it at all, so you should probably be doing some hardcore reflecting and figuring out what you can and can't deal with, too.
There are all kinds of "coming out" stories around the forum. Reading around a bit might help you figure stuff out, too. Your husband could also learn some stuff by reading, so inviting him to join you in researching may be a great way to help break the ice and get him to start thinking about it a bit more.