Is a size 15? Shops?

Not sure how sizing works in Austrialia, but here in the US odd sizes are in the juniors (teenagers) department.

If your clothes are too big, but your still losing I would a few things you can wear. I would look for things that can be belted when you lose more weight like a wrap dress. Wrap dresses are amazing. I have one in black that I wear for job interviews and I have been able to wear it through several weight changes.