My bump has got smaller?

Natalie • Pregnant with my third baby :) couldn't be happier. Roll on August 2016!
Hey girls.
So I'm 22 weeks and 2 days to be exact today. 
My sister-in-law made a comment about me looking smaller than when she last saw me. 
I didn't really think too much on it. 
But today myself and my partner have both noticed a huge difference! I was pretty big in size a couple of weeks a go, and have always been showing a lot since early stages.
Didn't know if this was normal?
Baby girl is moving about now and then, so I'm not concerned about movements. However just seemed weird that I now look about 16 weeks pregnant again!
Any comments are really appreciated!
Thank you in advance x