No sweat, generally speaking this is nothing to worry about.
In almost 100% of occurrences involving a server error or game crash at the point of opening a Card Pack the goods are still delivered directly to your account.
It may appear as though you haven't received the goods for your Pack, because you weren't able to go through the process of flipping the cards and revealing the Cards / Items, but they should be in your inventory.
Do a full sweep of your cards, items, relics, and catalysts to see if anything new has arrived.
If you are seeing new Cards, Items, Catalysts, Relics, etc... chances are your goods were delivered properly despite the crash / server error.
If, however, you are certain that this is not the case, no need to worry just submit a ticket to our support team and we'll see the issue resolved ASAP!