An easy way to see that is going to the blizzard store log in to the account you used to buy the ticket and select to see the blizzcon online sale. If you can see it your account is fine.
Isheria's on the money here. That's definitely one way to double-check, another way would be to check the order history by logging into Battle.net > choosing Account (near the top) > Transaction History > Orders.
Apologies for the confusion we caused there! This email was sent incorrectly and was meant for those who purchased physical tickets. If you have purchased the Virtual Tickets and have confirmed this through one of the aforementioned steps, the streams will be available to you through your account when the broadcast goes live. Hope that helps!