Implantation cramps

Has anyone experienced constant dull cramping after implantation? I am pretty sure I implanted yesterday but I have had non stop dull cramps today. I am having a hard time deciphering whether or not these are just period cramps now. Everything I read seems to imply it would be off and on for up to three days. Not all day. Just curious if anyone else experienced this. I am trying to hold out for testing but am not able to turn of them endless scenarios in my mind in the meanwhile lol