Wrong size bra (pre BA)

Hi girls..
I was sat thinking last night about the amount of girls who wear the wrong size bra.. and I'm one of them.. lol

i think I'm going to go get measured properly tomorrow.. I haven't had
BA.. but i have never had a fitting and always bought my bras from the
warehouse (like your asda) cheap and crappy.. lol

The bra I'm in right now is a sports bra.. not tight enough in the band..
too loose in the cup.. not sure why i bother wearing it as there is no
support. Size 12C (UK-34D)
My going out bra.. a bit of a push up bra.. is nice around the back..
but the the wires don't fit my cup properly so they get a bit squashed
out of shape. that is a 12B (UK-34C)
so maybe i am a size 10 (UK-32) band instead.. and still a C cup (UK-D)??

I have tried looking at websites that tell you how to measure properly.. but they all say different things, so I'm even more confused.

Just wanted to know if anyone is clued up on this.. can you tell me what size.. estimates.. to take into the change room.
I absolutely HATE shopping with a passion.. and its winter here.. so will be cold getting my kit off.... brrrrrr.. lol.. and if i kind of know what band size or cup size to look for it will help speed it all up.
(plus i will have 1 boy child and 1 girl child with me.. hahahaha (and my son loves to put bras on his head and walk around)

Rib size - 29 inches
bust - 35 inches
over bust - 34 inches

thanks girls..

dont nother looking at online sites, they r completly crap!!! it sounds like th band is too big n the cup size is too big, so i think try going down a bnd size, n cup size. Though u may find when u go down a band size, bigger cup sizes will fit u as this tends to be the case! xx

I'd say from the sizes you've mentioned your wearing a band size far too big. I think you'd probably be more like a 30E in uk sizes or an 8DD in AUS/NZ sizes. That would make the band size a better fit and the cup sizes should be wide enough to fit around your breast properly.

but if i tried on a DD.. the cup would flap about and there would be enough room in there for another whole person.. lol

i will definately try the 8 - 10 bands.. and see where that gets me

A DD in a 12DD (34E UK) would be huge on you. The general rule is go down a band size but go up a cup size.
I'm a 32FF or 10E but if I wore a 12E it would be too big in the cup because if you go up a cup size you also need to come down a band size. So if you were a 12 band you would need to wear a 12B/C but as you are not that size it wouldn't fit properly anyway