Probably just your meter. Any measurement is likely to be within + or - 0.5. They are not entirely accurate. If you felt weird and were worrying that will raise you BG also. Quite considerably in fact. One of the highest readings I've had over 4 mmol higher than what I would expect was a reading I took at a petrol station while worrying I was going to be late for a meeting because I got stuck in traffic.
There is something to this testing can cause you to worry thing. If I get an unexpected high reading and then it appears to continue forward to further readings and they are raised I simply stop all tests for a day and eat very low carb as I know that won't hurt me and try to chill. I tend to find as soon as you stop worrying the levels drop back to normal.
The other reason for raised levels can be that you are fighting off a bug even if the bug or virus hasn't actually produced any symptoms.
Now you do know about Dawn Phenomenon (DP) that we ALL get ? That's where the level you wake up in the morning with is far higher than when you went to bed. If you need that explained just ask. As I say we all get that to a smaller or larger degree. It will probably be larger for you as newly diagnosed.