Flossed my new veneers for the first time and they feel less secure. Is this a normal problem with new veneers? (Photo)

I just got my new set of veneers (top 8) a week ago and flossed for the first time today. It was going smooth until I got to the gap in between the back two and the floss wouldn't go through. I added slight pressure and it went through but got stuck. After I tried to pull out the floss I heard a crack. So out of fear of ripping out my teeth I cut the floss loose. But now my set feels less secure and the back tooth I heard crack is slightly different on my bite. Is this a normal problem with new veneers?