For me my boobs starting to fill out and change colour was the first sign of pregnancy, that and morning sickness. They haven't really hurt much for me yet, just been really sensitive some days.
They hurt entire first trimester and half of 2nd then stopped and now in the third they started getting sore again. Haven't grown at all though.
I can't even pin point a week at this point that it happened. All I know is now they're spilling out of every bra and constantly sore. 😅