Add 2 week trial to a monthly subscription plan

my_pmpro_profile_start_date.php

//change the profile start date
function my_pmpro_profile_start_date($date, $order)
{	
	if($order->membership_id  == 1)
		$date = date("Y-m-d", strtotime("+ 14 Days")) . "T0:0:0";
 
	return $date;
}
add_filter("pmpro_profile_start_date", "my_pmpro_profile_start_date", 10, 2);
 
//change the level cost text
function my_pmpro_level_cost_text($cost, $level)
{
	if($level->id == 1)
	{		
		$cost = str_replace("Month.", "Month", $cost);
		$cost .= " after your <strong>2 week trial</strong>.";
	}
 
	return $cost;
}
add_filter("pmpro_level_cost_text", "my_pmpro_level_cost_text", 10, 2);
 
//remove any trial we might already have on the level (especially important for Authorize.net users since we add a trial to all levels)
function my_pmpro_subscribe_order($order, $gateway)
{
	//are we overriding the trial for this level?
	if($order->membership_id  == 1)
	{
		//remove the trial we add to Authorize.net levels
		$order->TrialBillingCycles = 0;			
	}
 
	return $order;
}
add_filter("pmpro_subscribe_order", "my_pmpro_subscribe_order", 10, 2);
Update