Please can you tell me how to cancel a link preview? I never intended to cause anyone trauma or fear.

It's a really common issue, one I've learned mostly deal with out of sheer necessity, but every time there's a new vaccine or something and a bunch of people start sharing articles with needles in their preview pictures, they add up. The frustration was not towards any single person.

Can't do it on an existing post, but in the future, wait for the link card to appear under the text, then hit the little X at the top right. You'll have a working link but no preview.