Here is a methodology to find it:
Prepare a white screen on you computer, for example a white document in GIMP.
Take an out-of-focus photo, for example, focus at infinity and the widest aperture to avoid vignetting.
Use different settings. Overexpose until the histogram is almost to the right. Underexpose until the histogram is almost to the left.
Open the images in Photoshop (or whatever) and using Levels, drag the opposite level a lot to contrast the almost white and almost black images.
If you see the pattern of what you video looked, yes probably you did.
If not, good for you.
Please post your results here so we know!