One of my first indications that I was pregnant was my sore boobs
but at about 6 weeks that subsided, i'm now in my 9th week and yes they are still very sensitive and if I catch anything (like that blasted doorframe

) then it hurts bad but they are no where near as sore as they were, so there is hope.
For bra fitting get down to your nearest maternity wear stockist and get measured properly for a good support bra.
The large majority of women wear the wrong size bra.
I wore a 38 c for ages then it got uncomfortable so I went up to a 42 c only to find after been measured (after years of been not quite comfortable) that I am really a 40 dd (at 9 weeks pregnant I am now a 40e

) also e and f cups are easier to find than ddd.
Congrats and good luck