All Tall Shy Guys I need your Help!!!! Please?

Ok Well I like this guy and I think he likes me. he is prettty tall and we would talk(message each other on myspace) and all of a sudden he stoped replying back to me. I'm Short and a little chubby. What do I do I noticed that Be fore i would jusst tap my fingers and my feet in homeroom and now he doe it to. Is he just playin around or does he lke me I get shy around boys WHta can and Should I do???