Cramp on only one side???

This sounds random but every period my cramps are almost entirely on my right side. Sometimes it spread across my lower abdomen but it always starts in the exact same spot. It's been like this for sometime now. I have painful periods so like it’s also difficult to sleep on my right side for long or like lie down on that side. Has anyone else's cramps always been one-sided and id you ever find out why this happens. Hope this is normal