Uy, normal lang yan sis! Day 6 pa lang kasi, and your body is still recovering from surgery, ang spine mo naman ay affected ng anesthesia and the whole positioning during CS, so konting soreness is totally expected. A few of us had the same experience, and it usually goes away after 1-2 weeks once you start moving around more at hindi ka na ganitong sore everywhere. But if the pain gets sharper or doesn't improve by next week, better check with your OB para sure, especially since back pain can sometimes be a sign of something like spinal headache from the epidural, rare pero mas safe na i-confirm lang!