I think you have problem with js try the below urls it may solve your problems,
<script src="http://fullcalendar.io/js/fullcalendar-2.1.1/lib/moment.min.js"></script>
<script src="http://fullcalendar.io/js/fullcalendar-2.1.1/lib/jquery.min.js"></script>
<script src="http://fullcalendar.io/js/fullcalendar-2.1.1/lib/jquery-ui.custom.min.js"></script>
<script src="http://fullcalendar.io/js/fullcalendar-2.1.1/fullcalendar.min.js"></script>
<script>
$(document).ready(function() {
$('#calendar').fullCalendar({
defaultDate: '2014-09-12',
editable: true,
eventLimit: true, // allow "more" link when too many events
});
});
</script>
If the above code works then download the js files used in script tag