Joomla session variables and retrieving wrong values - php

Question

I'm doing some custom coding for a Joomla installation that uses jReviews.
In a module on my home page I pass an array of content id's to a session variable (step 1) and then in other pages such as Top Products or Special Offers I might send a different set of values to the same session variable (step 2), each time the values are related to certain attributes, something like a 'related products' function. When finally I view a product, I should get the values sent in step 2 but instead, I'm getting the values from step 1.
This is what I'm doing:
Step 1:
$db =& JFactory::getDBO();
$query = "select * from jos_jreviews_content jrc
join jos_content jc on jrc.contentid = jc.id
where jc.state=1 and jc.catid=10 order by jc.id desc limit 100";
//state 1= published, catid 10= products,
$db->setQuery($query);
$allproducts = $db->loadObjectList();
$nav_session = JFactory::getSession();
$nav_listings_ids = array();
if(count($allproducts)) {
$i=0;
foreach($allproducts as $relatedproduct) {
$listingid = $relatedproduct->id;
$alias = $relatedproduct->alias;
$nav_listings_ids[$i]["id"] = $relatedproduct->contentid;
$nav_listings_ids[$i]["link"] = "index.php?option=com_content&view=article&catid=10:products&id=".$listingid.":".$alias."&Itemid=16";
$nav_listings_ids[$i]["title"] = $relatedproduct->title;
$i++;
}
}
// Save to session var
$nav_session->set('related_results_listings', $nav_listings_ids);
Step 2:
$jrcompanyname = '*'.$listing['Field']['pairs']['jr_companyname']['value'][0].'*';
$db =& JFactory::getDBO();
$query = "select * from jos_jreviews_content jrc
join jos_content jc on jrc.contentid = jc.id
where jrc.jr_companyname = '".$jrcompanyname."' and jc.state=1 and jc.catid=10 order by jrc.contentid desc";
$db->setQuery($query);
$relatedproducts = $db->loadObjectList();
$nav_session = JFactory::getSession();
$nav_listings_ids = array();
if(count($relatedproducts)) {
$i=0;
foreach($relatedproducts as $relatedproduct) {
$listingid = $relatedproduct->id;
$alias = $relatedproduct->alias;
$nav_listings_ids[$i]["id"] = $relatedproduct->contentid;
$nav_listings_ids[$i]["link"] = "index.php?option=com_content&view=article&catid=10:products&id=".$listingid.":".$alias."&Itemid=16";
$nav_listings_ids[$i]["title"] = $relatedproduct->title;
$i++;
}
}
// Save session
$nav_session->set('related_results_listings', $nav_listings_ids);
On my product page I loop through the values of $_SESSION['related_results_listings'] to find the position of the item I'm viewing:
$nav_session = JFactory::getSession();
$nav_listings = $nav_session->get("related_results_listings");
// Locate the current listing in the search results list and retrieve the previous and next items
$index = 0;
for( $i=0; $i<count($nav_listings); $i++ )
{
if( $nav_listings[$i]["id"] == $listing['Listing']['listing_id'] )
{
$index = $i;
break;
}
}
I'll be glad to explain any of the above if someone is willing to help me out. Thanks in advance and Happy New Year to all!