fluctuating hormones are a bitch!
I'm of a similar age too and although I'm losing weight well I've had days when my weights gone up even though i know I've not eaten enough calories to be a culprit. I've found I need to be really careful with salt as i retain fluid. this does come off but its very disheartening to see. I retain when I ovulate too and when I'm pre-menstrual - fluctuating hormones are a bitch.