i thnk When your heart beats faster and slower at the same time. When your stomach get butterflies every time you see him or hear his voice. You find yourself thinking about this person all the time. You can just feel your face start to get hot and you cant help but smile when you think about him. I know this probably sounds super cheshe but it's true. I hope this helps!
1 st symptom is you will loose your concentration from work 
2nd symptom you will start smiling without any reason
3rd symptom every time you will think of your crash 
4th symptom your main activity will create special attention for yourself from your love.
and when you talk to her you think that she will understand your love in your words .
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