As far as I was aware, the standard protocol is not opening presents on the day but having them proudly on display throughout the reception on one or two groaning tables of shiny, which then get bundled into someone's large-booted vehicle at the end of the day/evening. Then the bride and groom open them at their leisure in private. A few weeks later they send out thankyou notes.

You are very bad for not sending out thankyou notes!!!