You still have to say that, that you want to talk about last week but don't know how to start. She cannot read your mind. For all you know "nothing" much happened or she didn't notice (you kept talking like "normal"), etc. In therapy you have to talk about and bring up what bothers you and what you want to talk about, not what you wish bothered your T. I would have started with talking about how difficult the day at work was because of all the flashbacks, for example, what you told us here (you can tell us your difficulties but not T?)