One of the things that I did know might happen was the separation of my abdominal muscles. I noticed last week that when I was lying down, and lifted my head up, I could see a little lump going straight down my midsection, so I figured it was starting to happen. (Apparently the lump is the rest of your insides poking through the separation between your muscles)
When I did the same thing last night, though, I got quite a fright! My muscles seem to have separated quite a lot, so I could now see a lump about two inches wide running straight down my middle.
Weird. Really, really weird.