Wow, I don't see Pinkie Pie mad very often. D: Nice drawing, you're awesome at pony anatomy. I'm still trying to figure it out. It's kinda simple, but easy to mess up.
Actually for me the more simple the harder, it can be very difficult to put things in the right place. Like yesterday I was working on another pony and I just couldn't get her nostrils straight. I worked on just that for like 15 minutes!