Can anyone relate?

I don’t know if it’s just me but I would like to know that this is normal. A few days to my period I eat like a cow, feasting on whatever comes my way and then the period comes and my tummy is entirely locked, I barely finish a sandwich, I can eat a bowl of cereal for the entire day, a few days after the period my stomach is still remains blocked, I crave things but when I get them I can’t eat it. In this period I loose a lot of weight (because my period lasts about 6days and then about 4days of not having appetite) if anyone goes through this I would like help on how to get this fixed.