Cutie mark crisis

Prologue: What’s wrong Rainbow?
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It's another beautiful day in Equestria. Pinkie Pie is throwing a party for her friends. Everyone is dancing, laughing and having a good time. Then Applejack gets an idea:
''Let's go to the beach! I heard that the water is really warm today.''
Twilight gets excited: ''Yea let's go, I could sunbathe and read my new book!''
''I'll take some cake so we don't starve there'', Pinkie suggests.
''Do I have to come?'', says voice silently from the stairway, It's Rainbow Dash.
''Why wouldn't you sugarcube?'', Applejack says wondering.
''Well... Umm... I... Don't like water.'', says Rainbow Dash and seems to be getting a little nervous.
''You don't have to go to water, you can stay at the beach.''
''I don't want to come! You can go without me!''
''Come on Rainbow, It'll be fun!''
Rainbow Dash thinks a moment and then says:
''Fine, but I am not going near the water, okay?''
''Okay, main thing is that you are there.'' says Twilight joyfully.

Pony friends start packing their stuff and walking towards the beach. Rainbow doesn't seem that happy about going. When they have walked about half of the way, Fluttershy breaks the silence by asking:
''So Rainbow, since when have you not liked water?''
''Yea, tell us Rainbow, I remember you loved swimming.'' Rarity notes.
''Can't a pony change her mind?'' Rainbow says with an angry tone.
''Sorry, I was just asking.'' Fluttershy apologies.

Finally they have arrived at the beach and everypony is having a blast. Even Rainbow Dash is now smiling a bit. But still she seems pretty sad when looking other ponies playing in the water and Applejack notices it.
''Is something wrong sugarcube?'' Applejack tries to ask.
''Nothing. I just... well.. nothing.'' Rainbow mumbles quietly.
''You can tell me.'' Applejack tries again.
''No i can't... I mean.. because nothing is wrong! Stop asking me questions!'' Rainbow says and starts to look pretty angry.
''Okay, no need to start yelling. I was just making sure, but are you sure you don't want to come in the water, you can just walk on the shore.''
''It's that nice?'' Rainbow asks.
''Yup.''
''Fine, but I am not swimming.''
''No need to, Come on.''
They walk to the water just that much that their hooves are covered on water. Rainbow looks at the water and smiles a little.
''The water is really warm''
''Told ya'' says Applejack proudly.
''Hey, you got Rainbow in water. Want some cake?'' Says Pinkie with a wet cake on top of his head.
''No thanks, maybe later'' Applejack says and looks at the wet cake.
''How about you Rainbow Dash?''
Rainbow is not responding. She is just watching the water like she would have not seen water ever before.
''Umm.. Rainbow Dash?'' Pinkie Pie says worried.
''Wha..Oh...No thanks.''
''Okay.''
Then suddenly dark clouds start hovering over the beach.
''Oh no!'' Rainbow Dash screams like she would have seen a ghost.
''What's wrong?!'' Twilight asks. ''What is wrong?''
Without any answer Rainbow Dash flies faster than light inside the lighthouse and the other ponies followed her inside. Inside everypony starte staring at Rainbow Dash. She stares at the ground and looks like she couldn’t breathe.
‘’What was all about? I thought you liked flying in the rain.’’ Applejack said shocked.
Rainbow Dash looks at her flank, then she looks her friends quickly and starts crying and runs to the top of the light house.
‘’Come back!’’ Fluttershy tries to stop her but she is not fast enough.
When they reach the top of the lighthouse they can see a blue wing disappear behind the clouds.
‘’What in darn nation is wrong with that pony?’’ Applejack says wondering.
‘’I don’t know but let’s give her some time and maybe she’ll tell us’’ Twilight suggests.
‘’Okay, maybe she just needs some time.’’ Rarity notes