Hi Beth, I think I had the same thing... I only found out at my 32 week check up, but my Dr didnt seem that concerned - she didnt even tell me what its name was!!
She asked me to try and sit up (from lying down) and that was how she could easily tell, as when I strained you could see that my abdominal muscles had moved to each side of my belly. She said that would explain why my whole belly was poking so far forward, and also why my back pain was getting very bad. She recommended as a method of supporting my belly to buy some large supportive bikepants, and pull them all the way up over my belly to under my breasts, just for a little extra support.

Hopefully the physio can give you more tips on how to make things easier on your back etc...