First of all, I must say, this must be the most cutest, the most prettiest, and the greatest Pinkie Pie cosplay ever. I really love the hair and the wig! They make you look so adorable! And the balloon(is it a clip if I may ask?) goes with it too.
Secondly, your outfit. The shirt and the necklace are perfect. Out comes your inner Pinkie Pie. :aw:
Lastly, I love how you have a mini Pinkie Pie. It just makes your cosplay spell out a-d-o-r-a-b-l-e!
So yeah, every thing about this cosplay is extremely cute and well done indeed!