I just posted a reply to the Nervous Nellie brigade assembling in the comments of the last chapter and all I can say is, read the label!
I have never seen fit to write a warning on a story before, but in this case I did, with some very specific guidelines. I also gave nervous readers the option of spoiling the plot for them privately if they want it spoiled. So everybody's got a choice here!
And just as a point of interest, I have personal knowledge and experience of retrograde amnesia (amnesia that occurs from the point of injury backward). I once was hired to perform in a wedding ceremony as the singer and got all gussied up (ended up in the same color dress as the bridesmaids, peculiarly enough), and the wedding was a second marriage for two forty-somethings who were living together but wanted to confirm a commitment. They arranged their wedding on a boat, which I believe was a medium-sized yacht, in Lake Union in Seattle. While the bride was going to and fro up the gangplank before dressing for the ceremony, she tripped over her shoe and landed in the lake, getting a rather savage bump on the head in the process. After taking some aspirin and temporarily attiring herself in my change of clothes which I had handy, they decided to go on with it, and the ceremony proceeded per normal followed by a reception with about 40 people seated on the deck. I found out the following week that the bride soon began to suffer from severe headaches, and following the ceremony, promptly - forgot it, as well as the events of the previous couple of months, including the decision to marry. The marriage was annulled. I don't know if she ever retrieved her memory of that period of time, but it was enough to cancel one marriage!