Excruciating period pain

Hi y’all, so I’ve been having this issue for about 4 yrs now when I get my period my first or second day is always by far the worst. It’ll start with light cramping up front and move to extreme cramping where I can’t keep my legs still I’m screaming and crying and not even pain killers work. The pain sometimes will go from my lower back where my spinal cord around my side to my front. The pain feels deep within. Please help this is very painful for me and I’m also having heavy periods. Tampons sometimes make my cramps bad.