I like your sense of humour.
Good that you still have one because I can feel the frustration. Do give ALL her food by hand even if it is messy.
If you are a smoker, try giving it up. I know, for any smokers out there, easier said than done. Consider that if anyone you work with smokes, the smell will be on your clothes.
Really try hard to keep the frustration out of your voice, some dogs hear the tone of your voice and react.
Your pup isn't much different in age to my boy, Roo, and Roo is going through a fear period where he enters the area where we go for obedience with all his hackles up even though there isn't a dog anywhere near him.(Just in case.
) He also reacts badly towards the new pup that arrives in the middle of training, it's like ye Gods, that wasn't here before, I must destroy it. So, give Pearl time and lots of patience. You were gone, then bingo, you turn up again, a bit like Roo with the invading strange new pups. With my breed it can be people they start freaking out over as youngsters too. I showed dogs and suddenly one might decide it won't let judges handle it( in case they are axe murderers in disguise) and sometimes all you can do is leave them at home until they get over it.