Hello I'm hoping a bra interventionist can help me out. 
I measured myself and am wanting to order a new bra now. I measured 29.5 underneath 35 hanging down
I make that a 30DD??
I have one bra and have been uncomfortable for at least 10 years in my bras probs more like 20 - anyway yday morning to this one bra which is a 32b I moved it to tightest fastening on band and pulled the straps tighter then I scooped and pulled all skin and tissue into the cups. OMG! I was spilling out from cups with a cleavage and spilling out at sides with underarm fat (I'm a skinny size 8) in fact spilling out everywhere - so I definitely need a smaller band but bigger cups.
What amazed me though was how much more comfortable I felt but more how much better I look. I can't believe this!! It changed the shape of my whole upper body and it's not even the right size more the scooping effect - waist smaller, no droopy flat chest and generally deportment better plus look younger. Unreal. So a well fitting bra in the right size is going to be so much better.
The problem I have is I'm in Australia and ordering from Bravissimo which is expensive and will be tricky to return I think (no good bra places where I am) so want to check if a 30DD sounds a good start or should I go down to a 28 and up the cup size? I'm thinking a 28 may be uncomfortable??
Breasts are flat at top and low down on chest with most fullness at bottom of cup but with the scooping seems to be a LOT of tissue and skin under arms and to sides of ribs (never knew this was here before!)
Thanks in advance any help much appreciated.