CD 19 Symptoms

Samantha
I am on CD 19...    I'm having a lot of cramping and lower back pain...    what does everyone else's cycle look like around CD19???  Could this be implantation cramps??   is it just me getting sick??   I'm totally lost and have never felt like this mid cycle...   I literally feel like I'm about to start my period but that's still a week in a half away....   
HELP!