Let me try to help,
Your links contain petite women who make the prom dresses look outstanding.
I hope you have the same petite figure otherwise you may hate the dress later.
As regards price, go for the whites if your parents don't mind coughing the cash.
But if you are a msapere or economist,keep it coloured.After all,You may not wear the dress again and no one will know how much you spent if you don't keep the price tag on.