Period question! Is this normal?

I recently have started the contraceptive patch (for those who don't know it is three weeks on the patch and one week off - and this is when you get your period- rather like the pill)

I'm currently on the fourth week and the period pain I'm having is so intense!

I've got cramps all through my stomach, down to my groin, around the top of my thighs and cramping around my bottom too!?

I want to eat everything yet when I go to eat something I feel so sick I don't want it anymore.

It's making me so tired and my moods are awful!

Now, this isn't normal for me- normally they are fairly light with the occasional pitch for a pain.

Is is anything to worry about? Or is it just the effect of the patch?