Sorry OP, not trying to scare you at all, but you really do need to just go to your GP if you suspect diabetes, rather than asking on here and trying to figure it out yourself.
I don't mean to be harsh, but diabetes isn't something you can take lightly and put your faith in the MNers (wise though they are, they can't help you diagnose an illness).
By 'bury your head in the sand' I meant that you might chose to not see your GP based on what you read on here, which really isn't sensible, because no-one on here can tell you what you need to know.
Don't be scared about what type of test your child needs. They will likely start with a urine test, and if that shows nothing, they won't need to do anything else. If it shows glucose, then a finger prick might be all that is needed to confirm a diagnosis, and it really isn't bad, just a split second and it is done, and at least then you can be glad you caught it before it got serious.
You are not being silly, you are doing the right thing by getting your DC tested, and being a very good mum. Wishing you all the best and a negative result for your DC.