I think that you have reached a turning point in your life: if life is a path/road we walk along, you have reached a widening of the road; a natural lay-by lies alongside,; there is a stream, trickling from a natural spring; someone has fashioned a shaded resting place. In short: you have reached one of those points in life where you are being prompted/invited to halt, and to think.
And Bluewater has been the place for this wonderful moment.
Don't laugh: it's serious, and there is a reason for it.
I think you have been a harassed mum-of-three for a while now. You've spent a lot of time thinking your way into the other people around you: what do they want? what do they need? how can I get it for them? You are probably very good at this now. The down-side is that you spend a lot of time doing that, and have only a fraction of the time doing that for you.
In Bluewater your eye was drawn to women who look the way you imagine yourself wanting to be in some way: calm; with time to consider their bodies, appearance, and clothes. It's very rarely just about the clothes, and most usually about self-nurturing and self-attention.
There would have been lots of women there, and your eye almost certainly singled out styles that you found attractive - and that would probably suit you.
I think the experience is telling you that life is now granting you the time, space and permission to start cherishing your self, and your body, a little bit.
Also, Barbie-pink nail varnish is pretty fashionable at the moment, so don't take it off too quickly! Coral is an easier-to-wear shade, and is a modern classic. YSL do a great "couture" range: I'd advise having a look at those and then going to buy the Boots matchy-matchy shade.
And lastly: I love, love, love Bluewater. 
Agree that it isn't quite as shiny as it was. I still love it, though.