Not bad for your first attempt, though I'll point out some things you should avoid in the future:
1. The enlarged version is squished. From the looks of it, you must have just scaled it by hand without keeping the same proportions. As a result, the pixels became all messed up. The easiest way to do this is to just scale the sprite 300% with proportions locked, which depending on the program might make it blurry, in which case there'll probably be a setting to avoid that.
2. It looks like you used sprites from Gen 6. Stick with Gen 5. Those sprites are much easier to work with and come out the cleanest.
3. Your outlines look overpronounced and unnatural. The outlines of the original sprite shouldn't change except for color swaps, in which case should still have the same style just with different colors of the same gradient progression.
That should cover everything I'm seeing. There are some misplaced pixels and weird feature placement here and there, but that all comes with practice. Good to see you giving this a try and I hope to see you do it more with better results!