Hello Lianne2209, it's not just you being silly. Diabetes does mean making a lot of adjustments to the way you live your life and everyone on this forum understands that.
From my experience, blood sugar levels being too high or too low will have an adverse effect on mood, but as you get things under control a bit more, this gets better and you understand a little more why you feel the way you do.
I would say if you can, try to make the effort to eat regular meals instead of just snacking. It's really easy for me to just type that without knowing anything about your circumstances, but I think that and the carb counting course will be a first step to better overall control.
And better control will make you feel better.