Lowe back pains?

Rachael
So this week was O week. My lower back (left side) has been bothering me for the last week. Today, I started getting pain in the front, lower part of my stomach? I thought my back pain was a result of a workout from last week, but today the pain moved to my stomach/abdominal. Have any of you experienced this?
I am currently on CD17 so I am almost confident it is not a pregnancy, but I just found the pain to be odd..