Often touted as the epic story of the Old South, Gone With the Wind focuses almost entirely on the Civil War (1861-65) and the years immediately following, ending around 1872.
Gums can be healed quite easily. For instance I was having receding gums. My dentist asked what kind of toothbrush I use, I told him a hard one. I felt like it cleaned my teeth better. Turns out hard is for dentures only, and otherwise all people should use soft. My gums grew back in a couple months.
One side effect of Zoom Teeth whitening (or other types of in-office teeth whitening) can be a chemical burn to the gum. At this point I think the best thing to do would be to let it heal for about 2 weeks. You have done an excellent job photographing the progress.