Node JS Sencha Ext JS Ajax Request Pending

Its my first time to use these two technologies together. Im basing my project with this https://github.com/tsuryap/ExtJsAndNodeExample

Everything is going smoothly. But then I tried doing a login module.

Ext JS would send the data via Ext.Ajax.Request

Ext.Ajax.request({
        url: '/userLogin',
        params:{
            username: user,
            password: hexedPass
        }
.....

In the Node server side it processes the data the login function that I made and calls a callback the return the response. I placed the console log just for checking purposes

app.post('/userLogin', function(req, res){
  userLogin.login(connection, req, form, function(data){
      console.log('READY TO SEND DATA');
      return res.end(data);   
  });

});

So I tried testing it and i found a weird behavior. First I entered a wrong username and password

Username : a
Password : b
Log : ('READY TO SEND DATA')

Then I tried the Second Time again with wrong credentials

Username : x
Password : x
Log : ('READY TO SEND DATA')
      ('READY TO SEND DATA')
      ('READY TO SEND DATA')

I noticed that my second request processed two times and I tried doing a third one but it just keeps on increasing in number.

Furthermore sometimes the ajax request becomes pending even though my console log showed ('READY TO SEND DATA')

I also tried res.send and res.json But it gives me a Can't set headers after they are sent. Error

Please help Thank You

via Juan Carlos Cabotaje