Hi Jaura,
Welcome - and what took you so long?
I'm at two months and have noticed a similiar experience. I think it really helps to track your daily units in your signature, like many do here, to see if there's a pattern on those days. It's also important to remember it's still very early in the program for both of us, that our progress is not necessarily a straight decline, and may go up and down. Some days I feel the off switch, some days I don't. Usually the latter happens when I have something on my mind that I don't want to deal with, so it's back to old comfortable patterns trying to use alcohol to numb myself.
Just stay on course, keep taking Nal, and be patient. It's good to be aware and concerned, but in another month or so, the situation may well have resolved itself, so don't let yourself get too worked up about it.
Hang in there and keep posting...
Sheryl