While you don't want to overuse Lorazepam/Ativan, you don't want to underuse it either. What I mean is, don't take only when your anxiety level is "situation critical." For quite some time I was very reluctant/fearful to take my Ativan unless things were really bad. Don't make the same mistake. You have to find a happy medium. For example, if you're going into a stressful situation and feel you would benefit by taking one of your pills, then do it. However, consider taking half a pill in those situations. Even just .5 mg of Ativan is often enough in situations like that. If things are really bad, go with a whole pill. I hope that helps.
Could be. Everyone has a different experience with drugs that affect the brain. It's a sedating drug, so you could very well have something like a hangover. You might get over this or you might not, and it could also have nothing at all to do with the medication. The only way you'll know is if you take it a few times and the same thing happens every time. By the way, you have a wise doc in that you know not to take this medication on a regular basis but only when absolutely necessary.