Hi Owen,
Are there any error messages in your console during runtime? Have you already compared your code to the Lecture Project Changes which can be found in the Resources of this lecture? And have you already tried to add Debug.Logs to your code to see what is going on during runtime? Maybe the assigned values in the OnClick fields of your Buttons do not match the respective index of the expected question.
See also:
- Forum User Guides : How to apply code formatting within your post
- Forum User Guides : How to mark a topic as solved