Yup, it's completely bollocks - I get it whether lying, or sitting - feels like my 3 x cs scar is about to burst and then I realise that 'oh no, it's just because it's a BH!' I'm seriously such a twat. Thank God I only have 2 and a bit weeks to go maximum!
A bit like a cross between a bad stitch and being stabbed? Thought it was just me lol. Sometimes I am just sitting there watching tv and it starts, or other times its when I turn in bed. Its agony. Can't remember having it all the other times.