Actually, they said that from the start that Amy started having a crush on Sonic when he saved her from Robotnik and Metal Sonic in Sonic CD.
shutup and just go watch Toradora or something like that.
No, he doesn't.
Yes he does but he is shy to declare his feelings
the reason why is because when they first met Amy thought that sonic and her would be a forever couple sense they were little,and because he saved her