Hi and welcome to the forum, inkompetentgirl!
Can you post the log from that burn?
If you used DVD Flick and had ImgBurn selected as the burning engine, the log is saved in the same location as your project destination folder.
You should see the location in the lower left corner of the main screen of DVD Flick. In this example it's named 'C:\Users\Cynthia\Documents\dvd'.
Open up a Windows Explorer window and browse to the project destination folder.
The ImgBurn log is the file named 'imgburn_write.txt'.
Double click on that file to open up the log in the associated text reader, such as Notepad.