A protocol for moving forward:
0. Double check the work to make sure that there are no other problems within it.
1. Alert the relevant parties.
2. Take responsibility for what went wrong. This doesn’t mean that you intentionally did it wrong, or that doing it right was part of your job description. It means that you know something went wrong, you’re unhappy about it, and you accept responsibility for letting it get by you and you accept responsibility for making sure it won’t happen again.
3. Apologize. Not because it’s your fault, but because the incident cost other people time or money or upset them, and you’re sorry that they have to deal with that.
4. Come up with a plan to ameliorate the impact of the problem. If you can’t come up with a plan, say so and ask for suggestions.
5. Come up with a plan to avoid the problem in the future.
6. Gather feedback.
7. Thank everyone for their patience and goodwill.
Either that, or you could hide, dissemble, blame, shuffle along, scowl, depersonalize and then move on.