Hi there,
There is a great book (and app) that describe these stages perfectly. It is called "the wonder weeks" (
www.thewonderweeks.com/ ). I have a kindle so I got mine from Amazon (which is cheaper than the hard copy). It describes all of these fussy periods, the reason behind it and also gives some suggestions and solutions.
It boils down to the fact that, in the same way a little one's body goes through growth spurts, his or her brain also does the same and each one opens up a whole new world for them. They will then get fussy because everything is experienced differently.
There's a great group on Facebook also for this - lots of women going through the same.
Good luck with yours!!