Depending on what your bg was before the meal started, that may have been pretty perfect as a bolus for that meal. Assuming it was in the 80-90 range, I think you nailed that meal. Although if you don’t want to eat the cheese, you could start decreasing that amount a little. Good test.
As far as worrying about the pen being inaccurate with less than one unit, you should not worry about that. I did a test on a scientific balance and assuming you prime your needle the pens, both the cheap looking plastic ones and the nicer replaceable cartridge pens are suprisingly accurate in their dosing even down the the lowest dose you can dial in.