Multiple different shopping cart instances

[eluser]TheManT[/eluser]
I've discovered something.
When i login (new session) and add items to cart1 and show cart2, the cart2 dont have any item i've added in cart1.
But if i refresh the page, the cart2 comes with the items...

So, i thing i have to load ALL the carts at the first time (when i login for example) e then just use the reference.
Even if i use new CI_Cart, in the second time it comes with values from the other cart...

I think the constructor method get the values from the session...

Am i right?