All you did was the quick kiss on her lips? No other kissing?
You are not at risk for oral herpes from kissing her chest, and if all you did was very briefly kiss her, I wouldn't worry at all.
I don't know if this will help or hurt, but about half the adult population has oral hsv1. You've quite likely been exposed already. Your parents, grandparents, aunts, uncles, etc., may all have it. If you share drinks, eating utensils, etc., you can get it. (You are more likely to get a cold or the flu, so don't do this.)
Oral hsv1 is hard to avoid, and in the big picture, not a big deal. If you have some kind of phobia about it, or germ anxiety, talk to your doctor about that for some relief.
You are risk-free. You re safe. Nothing has happened.
Well, it is definitely a negligible risk.
I can confirm that your dry mouth has nothing to do with stds.
I am 100% sure that you are okay :) Don't worry.
Imagine if everyone would worry because of the events you described? :D
I know her for quite sometime now