Implantation cramping at 7-8DPO??

I’m 8dpo and had some cramping on 7dpo, but consistent, dull cramping for about 4 hours now this morning. I thought maybe it was gas, but don’t have any and already had a BM, so I’m thinking that maybe this is implantation cramping... I’m trying not to symptom spot but I soooo want to be successful this cycle. I’m not due for AF until Monday, so I don’t think these cramps are AF related, although anything is possible. Has anyone had actual implantation cramping and tested positive soon after? How long did the cramping last?