What can i wear for a family party? Any links for a new dress?

I love heels. Like tiny ish ones. Not pole dancing high or a inch. Just about 2 inches. Comfortable heels. Were going out for a 84th party, 43rd party and a 30th birthday party. All on the same night. (joint birthdays) i want to look nice. But i want a new dress. Im thinking of a LBD (little black dress) with black heels and a sparkly jacket with think grey/black tights. Ill accessorise it so i don't look like a goth. Im 14, but i want to look cly. It's autumn in the UK so im wearing tights because it can be quite chilly. I have �30 :-) x