Goodluck with today, i'm sure you felt as if it was Niamhs very first day at school, and it will probably feel like one of the longest until she comes home this afternoon, thats how it felt for me.
Regarding your nurse insisting Niamh doing her own injections at this early stage, i feel, is really not her discission to make. A child has a lot to deal with, and doing your own injections is pretty daunting and scary thing for anyone, more so for a child. Andrew was diagnosed at 7 in the Feb and took him to the following July when he was 8, whilst at diabetic camp to find the courage to do his own. Even a resent stay in hospital found him insisting on doing his own injections, he won't let me near him with a barge pole, let alone a needle!!
So i wouldn't put any pressure on her, you'll both know when the time is right, and setting a time for her to become independant, like a school holiday, ie Easter/Summer would give you both a more relaxed time to do so.
Let us know her insulin regime and we'll help with suggestions for diet and snacks, it can all be pretty daunting, but your already doing a marvellous job,
Take care,
Suzi x