Currently wearing a 36B but it feels too small. I've tried 34C but dont really fill the bra. I dont think I've ever seen a 38B. According to my tape measure I'm 32 Inches under my bust which means I'm supposed to add 4 as it's an even number so that's a 36. That bits fine but Around the front of my bust I also measure 36 inches which would make me AA cup, which I'm definitely not. I'm not big busted at all and I'm size 10-12 on my top half so I cant see how i could need a 38 band.
I've been to m&s before but never seem to get the right size from them. Where am I going wrong!