implantation

I've been crampy today... feeling small cramps that are unlike any cramps I've ever had. Just different. Low pelvic area. Has anyone ever experienced this before and it was implantation? Also I have had terrible heartburn for 3 days and I had a dizzy spell at work yesterday and a test this morning with a vvvvvvvfl. Was gunna retest tomorrow morning with pink dye tests because of the advice from others. Anyways what do you think?? I would be about 8dpo if I ovulated early like I think I did