I had the same thing with my first pregnancy around the same time until the baby grew considerably bigger.
I'm Currently 14w5d and have started to develop the same 2 bumps. A little low bump, then it looks like a tight elastic band around my waist at belly button level pulled in, then another bump above it.
Obviously the baby is too small at the moment, so it must be my organs (intestines etc pushing up, with a tight muscle band around my middle)
It's like 2 rolls as people call it with fat.
With my first pregnancy this went about 26 weeks.
Anyone else get this?