abdominal soreness.

Leidy
I had my twins 14 wks ago at 33 wks. I when I do certain activities I feel sores in my abdomen and I have to rest before I do anymore activities. Have any of you experienced this?  I'm wondering if this is normal after a c-sec specially since I had twins and my muscles and tendon stretched a lot. Sometimes the soreness occurs when I carry my twin each one individually. If I over stretch or bend down to get an object. Is this normal? It's my first c-sec so I have no idea if this is normal. 
Thanks.