Tabs within tabs not working properly using bootstrap 3 - php

Question

I am working on a webpage, where I plan to have to two menu tabs for one of the tabs on the Main-menu tab. I am able to get the Sub-menu tabs to show up on the page. The content gets populated properly for all the tabs. But, I am not able to navigate between the tabs. I am posting the code below of how I declared the tabs:
Header.php
<div class="row clearfix">
<div class="col-md-12 column">
<div class="tabbable boxed parentTabs" id="mainmenutab">
<ul class="nav nav-tabs">
<?php include "mainmenu_links.php"; ?>
<li class="dropdown" onclick="dropdownuserlogin()">
<?php include "userlogin.php"; ?>
</li>
</ul>
</div>
</div>
</div>
</div>
<script type="text/javascript" src="//netdna.bootstrapcdn.com/bootstrap/3.1.0/js/bootstrap.js"></script>
<script>
function dropdownuserlogin(e){
$('.dropdown-toggle').dropdown();
$('#userlogin').dropdown('toggle');
}
$("ul.nav-tabs a").click(function (e) {
e.preventDefault();
$(this).tab('show').addClass('active');
});
</script>
</body>
</html>
mainmenu_links.php:
<?php
$main = $_GET['main']; $sub = $_GET['sub']; /*echo $main; echo $sub;*/
$main_menu=array("Home"=>"files/home_page.php?main=1&sub=1",
"Submit a New Project"=>"files/form_page.php?main=2&sub=2",
"All Projects"=>"myday/.view_table.php?main=3&sub=1",
"Innovations"=>"files/ideafactory.php?main=4&sub=4",
"Share your learning"=>"files/shareyourlearning.php?main=5&sub=5",
"Meet the Team"=>"files/team.php?main=6&sub=6");
$i = 1;
foreach($main_menu as $key => $value){
if($i == "1"){
echo "<li class=\"active\"><a href=\"../".$value."\"";
if($main == "1" | $main==null){
echo " class=\"selected\"";
}
echo ">".$key."</a></li>";
}
else{
echo "<li><a href=\"../".$value."\"";
if($main == $i){
echo " class=\"selected\"";
}
echo ">".$key."</a></li>";
$i++;
}
}
?>
projects_menulinks.php
<?php
$main = $_GET['main']; $sub = $_GET['sub'];
$sub_menu=array("Myday"=>"myday/.view_table.php?main=3&sub=1",
"Techpulse"=>"techpulse/.view_table.php?main=3&sub=2",
"BrownBag Sessions"=>"brownbag/.view_table.php?main=3&sub=3");
$i = 1;
foreach($sub_menu as $key => $value){
if($sub == "1"){
echo "<li class=\"active\"><a href=\"../".$value."\"";
echo ">".$key."</a></li>";
}
else{
echo "<li><a href=\"../".$value."\"";
echo ">".$key."</a></li>";
}
}
?>
I think I am messing up something with the tabs declaration. Can someone please let me know what am I doing wrong.