Cramps... But only on one side

Go got my period yesterday (two days early) and I have the worst cramps today but there only on one side (right side) and it's incredibly painful, it's hurts to walk or move...  But yesterday I forgot to take my birth control in the morning and could still I got home so I was 8 hours late... But I don't know if that would do anything but I dont know what to do like I can't even move.., I haven't had cramps this bad since before I started my birth control