THis bit of "code" you posted :
if((username == "Admein") && (password == "12344")){
return true;
will not work. But you probably wrote
if((username[i] == "Admein") && (password[i] == "12344")){
return true;
which is why you MUST USE THE [code] [/code] tags around code so [i] shows instead of turning on italics.
until then it is too hard to read your code.