How do you feel when you have a crush on someone?

I feel like crap. 

I have a crush on someone rn, so I'm worried that I look bad 24/7. I'm also self conscious about everything I do. I can't look cute because I have to wear a stupid school uniform.. I also worry that I annoy him, or maybe he doesn't like my personality, hair, face, all that jive.

I have never had crush on someone. Actually for years i've had a difficult time understanding the concept of crush specially when this phrase got overwhelmed during my generation. Finally after checking many dictionaries i found an appropriate explanation which is

"A burning desire to be with someone who you find very attractive and extremely special"

Yet i am not sure of everyone having crushes following the same concept. Because there are many varied examples of such crushes i've seen around.

At the end, i'm wondered why it shouldn't be called "love" from the first place instead of such nonsense creation (to me of course).

I have a girlfriend, i love her and i feel my heart blowing out of my chest everytime i think about her. I guess that answers your question, cause apparently i have a crush on her too according to the definition!

Best description I ever heard of the early onset of romance was a song from The King and I called "Hello Young Lovers". Here's the bit you need...

I know how it feels to have wings on your heels
And to fly down the street in a trance
You fly down a street on a chance that you'll meet
And you meet not really by chance...