Hi sheshe, I'm just on my first period on the low carb diet and it's much the same as always, on time, short and heavy. Still have the sore tum and craving sweet things like a mad woman!!!
When I did LighterLife last year for 12 weeks my periods remained the same also, so I wasn't expecting any change in my cycle as this diet isn't a VLCD. Only on day 2 just now and I usually only have it for 3, maybe 4 days max, so I'll let you know if mines goes on longer than normal.
Maybe it's just your body re-adjusting to the new diet, we're all different, I've been lucky so far that no diet has really affected my totm, although had hoped they'd stop for a while when I did LL, but they didn't!
Fingers crossed next month you'll be back to normal babes x