I liked it
But I didn't love it.
It had a nice little progression to it. As many of these dream stories do. Liked the underwater bit, thought that was nice, but it could've been longer. I felt there was a lot more you could do, like him going back for his teddy or something.
And about that teddy. At the start, it just kinda appears when he flies off, it left me thinking "What? There's a teddy now? Oh! So he's younger than I first suspected." Honestly, it was a bit of a surprise to have your idea of a character altered so dramatically.
And, about the teddy even more. If your character is young enough to carry a teddy around with him, they carry it everywhere, and have a big attachment to it. So, if he were to drop it in the sea, he'd go back for it. Instead of just kinda discarding it like he did in the cartoon.
That bit jarred with me quite a bit.
There was one other thing that jarred with me. It was going along fine, with fanciful creatures and adventures and what-not. Set to a backing song which, although not the sort of stuff I choose to listen to, fitted very nicely and really added to the atmosphere of the flash. Then he gets on that flying sheep. And it bleets.
WHY did you decide to use a cheap sheep noise? None of the other creatures had a noise. It just confused me, and made me not drawn into the cartoon any more. In fact, it had the opposite effect.
Finally, the animation of the flying bit. It was just a tween across a background. I found that very cheap and shoddy. It just, showed that you didn't put a huge amount of effort into the finished product. Just 30 extra minutes could've sorted that out. Same with the seal diving into the water, it just looked badly animated. Either work on it so it looks good, or don't put it in.
Overall, well, it was pretty all right. But, it was far from amazing.