I would say that your change in lifestyle is indeed a huge factor in your period changes, and, you may find that these changes happen next month too, whilst your body is settling into your new regime.
Should these symptoms continue, however, you may wish to look at Agnus castus to help with heavy flow and cramps.
It may also be worth while looking at a B vitamin and/or a magnesium supplement to help support your body through any new routine.
Kindest regards and good luck with your 'new you'.
Do you have questions? Please feel free to ask.
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