Looby, I didn't say her dose was lower this morning....I said her pre-shot reading.

She is looking good at +5 but that probably wasn't her lowest reading because that is usually around +3 or +4 in the cycle and by +5 it's likely she is starting to go up again.
If you don't give insulin you don't need to do any testing in the middle of that cycle.
Some cats go lower at night than during the day but the key word there is "some". Every cat is different and that's why testing at the critical points in the cycle according to the insulin you are using is important. I don't think you need to worry about any more testing today until the pre-shot tonight.
Looby, my concern is that with Smiffy now getting some lower numbers, if she has a very active cycle during the day and she has her lowest reading at +3 or +4 but you don't test until +5, Smiffy could potentially go too low. Right now she is fine but that could change if her numbers keep dropping as they have been doing the past few days . Anytime there is a sudden drop in the readings, more vigilance is important to make sure kitty stays safe. You can control the insulin you give but if Smiffy's pancreas is starting to do some of the work again, you can't control that. I understand that your illness and routine make it hard to get a +3 or +4 reading during the day. Would it be possible to do a +2 test during the day then to see just how fast Smiffy's BG is dropping? I'm asking because I want to make sure Smiffy stays safe and Caninsulin can drop the BG quickly and by quite a bit by +3 in the cycle which is why we all keep talking about getting a reading at that time.