Possible autistic daughter

[FFSReallyreally]

I am wondering if my 6yr old DD is autistic. Up till now I have put it down to things like a very difficult start at school, being summer born, and hoped she would grow out of it, but she doesn't seem to be improving.
She has regular meltdowns, particularly after school, finds it difficult to regulate her emotions/frustrations, she finds it difficult to make friends, appears to be dependent on 7 and 4 yr old siblings and I suspect she mimics their behaviour. She is a terrible sleeper, fussy with her food, and she picks and chews at toys/ clothes etc.
She is however one of the kindest childen I have ever met, very empathetic and goes from one extreme to the other.
We have just moved house/ schools and she is finding it difficult.
What is the difference between a child who is socially awkward and why, and actually autistic?
I want to do the absolute best for her, and get her support if she needs it, and not wait for things to get worse. However DH is very much, he doesn't want to make a mountain out of a molehill, and does not want to get her assessed as she will feel labelled and it will make a big thing of it when it doesn't need to be.
What shall we do?

My DD was 6 when I asked school if she could be autistic..they laughed me off, she’s bright and summer born but with ASD in our wider family I kept it in mind and did lots of research and reading around how to support her. By age 9 she had awful year at school due to various issues and her anxiety was very high. Eventually over the last 6mths we pursued a private diagnosis as wait lists were 2-4yrs, it cost £2k but was carried out by NHS staff working privately too as she’s nearly 11 and struggling so so much with life and school. Yep she’s autistic no doubt, nothings changed at home but now we have a piece of paper to wave at school! Hopefully it will help secure more support for her as she’s goes to secondary school. I’d echo as above please keep pushing as once the hormones kick in she may well struggle more and more managing herself as the differences with her peers become more evident.
As aside you may well start to realise yourself or your DH are on the spectrum which is also an emotional rollercoaster. My DH struggled to see the need for a diagnosis at first but now it’s opened a whole can of worms helping him understand his life more as he realises he’s probably on the spectrum too.

I'll message you. There are all sorts of things that can be put in place, although you do need a good SENCO. We now have an absolutely brilliant one, but the one who was in place when we were applying for the EHCP told us that there were no adjustments available unless the child was two years behind academically or, I quote, "throwing chairs." This is not the case!