What is the Difference in Implantation Cramping & Ovulation Cramping?

Today I got a positive on a OPK test strip. And tonight terrible cramping. Feels like on both sides. But is VERY low in my abdomen area. Way below my belly on. My husband and I did BD last night & the day before. Is this more likely Ovulation Cramping or Implantation Cramping? How Soon does implantation cramping occur anyway? Thanks!! 10 points