How can I trigger a rules event by code ?
I managed to invoke the event "calculate sell price" by adding a rule with the event "When existin line item is updated" and then adding a call to rules_invoke_event() in PHP code like this:

rules_invoke_event("commerce_product_calculate_sell_price", $commerce_line_item);


I was previously calling this rule incorrectly, without adding the $commerce_line_item so this problem is resolved, now the shipping remained.
Thanks for your time!