Cerelle

Hi I started on cerelle about three weeks ago now and last Sunday I started my period. It started off really light but I’ve been constantly cramping for about a week now and I normally only have cramps for two days. Also I normally only bleed for five days and it’s now been really steady for 7. I guess this is just me body adjusting but I feel really tired from it. Any ideas when it should stop or when I should be worried? Thanks