Am I Acting Like an Idiot?

why don't people call when they say they will?  you give them your number they say, "I'll call you this weekend."  then they don't.  should i except the same from e-mail?  a guy gay for my e-mail address and tells me he'll send me a message over the weekend.  that was a week ago.  i see him at school.  he acts interested and still no message.  do i e-mail him?  how can i be in my age and still not know the rules?