The game itself seems executed well enough and is playable, but it isn't a well-polished game. It has a lot of potential.
For one thing, the spelling on the instructions page needs to be checked: "happiness"?
For another, the music should have neater looping. Currently it ends, and then starts over very abruptly, instead of smoothly looping.
The graphics are not only lacking, but inconsistent. Your cart, the well, and the dunes in the background are done in three different styles.
When the wind starts blowing, existing raindrops don't start drifting, which is just lazy and doesn't make sense.
The game also lacks a goal, benchmarks to beat/reach, powerups, etc...and the difficulty levels don't introduce anything new, just less rain and more lightning. Overall the replay value is low for repeating a game, and equally low for choosing a different difficulty. Play this game at any difficulty for 10 seconds and you've played it all.
This is a good game considering its your first, but as previously said its lacking in gameplay, maybe if you come back to this project you could add a story, objectives and better yet a shop, so as you collect water you can trade it in for upgrades, most people love that in flash games.
For your first game, This isn't half bad. The music was decent, the graphics were alright, but the actual gameplay was somewhat lacking. I think with a bit of polish and hard work, you may have some success as a game maker on here. Good luck!
it's a good start for development but not as a game for people