I have been given a tablet to take twice daily which is to encourage my knackered pancreas to create some insulin!
That suggests that you will need insulin anyway since the insulin secretagogues you are taking are, apparently since you still have high BG, not enough; the next step is insulin.
[Assuming you actually meant what you said rather than you just trying to be funny. Metformin, the first line oral treatment, does not "encourage the pancreas to create insulin"]
I'm really quite shocked that you havn't been given a clear diagnosis
Yeah, and we haven't found a cure for cancer because all the scientists are lazy, incompetent and just can't be bothered... Have you considered the possibility thar medicine might be *hard*? That doctors might not be doing it out of malice but because, unlike you, they are not omniscient? They are sending OP to have the tests done they need to distinguish between the two types after all.
As for the original question, given that you're asking here it's clear that you haven't been told when to start injecting insulin, and probably haven't been told how much and when either, so I don't really think that there is much point in randomly experimenting.
If you really wanted, though, the usual starting point is 10u Lantus/Levemir and 1u per 10g carbs Humalog/Novorapid (about 6u per meal assuming normal portion sizes).
This and
this document by NHS GGC should cover much of what you should have been told before being given the insulin pens.