Yes you're right, the dark pattern on the cap is not distinct enough to parse as rotating rather than moving back and forth.

Amazing work, and there can't be enough praise of style and technique. I have just one observation which is definitely not a critique. I do not see the rotation but rather that the mushroom is dancing on the edges of its base, always facing us with the same side. I notice that the different sizes of the spots on the top are suppose to show rotation but it is not clear enough, and I wonder what could be done to help? Slower animation with more frames to make it more obvious that all the wide and narrow spots are moving and into which direction? 

Feels so clean. Love the pastel feel and toon shading.

It's a mush, a loading screen mush!

I like this a lot.  Looks game ready to me.

I love this! Somehow it looks like it uses a lot more than the 11 colors, nice job

Really cute and the animation looks nice 

Cool mushroom!