advertising for advice.

I need advice. It's about prom night. And no,it's not about wheter I should go or not,because I am going. =)

I went prom dress shopping today, at the old building of MidValley Megamall.Yep,haven't explored The Gardens. =)

Anyway,rounding the whole shopping excavation (just like one man. =_= I got quite annoyed at one point because the dresses all wouldn't fit my size.) up, I came to a bottome line.

TWO DRESSES :

First dress:
*Bluish turquiouse-ish...just imagine Su Ping's blue dress's colour.
*from Phenomenal.
*last piece. I'm not sure for my size or all sizes..
*I super love it,more than the second dress I shall speak of later.
*halter neck.
*very expensive,comparatively.Double the price of the second piece.

mum says......
*good material
*probably needs alot of work,thus the price
*very sophisticated,compared to the second dress I shall speak of later.

Second dress:
*redish black.
*tube dress.
*It's pretty too....
*more normal and casual(?). I mean I can picture myself wearing it with jeans.XD
Well,you can clearly see that I absolutely love the blue one more.XD

mum says........
*not so good material.
*looks very young-ish..just for 17year old-ish ppl.
*more student like,cuz students shouldn't splurge on dresses so much.


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So,my problem is, I look nice in both dresses (mum and I agree) but I can't decide which I would buy.If they were of the same price I'd definitely grab the blue one,but the thing is their not. So now I don't know what to do. (=_=)

I only have a picture of the red one.


Help needed!!!! please help me out!!