Bangkok - Hong Kong - Shenzhen - Hong Kong - Bangok

Hi,
I'm Italian and I'd like to know if my trip is qualified to get 144 hours free transit for visiting Shenzhen.
I'm in Bangkok so I'll fly to Hong Kong for 5 days,then(if I'll get Visa)I'd like to visit Shenzhen for 5 days then go back to Hong Kong to catch the flight to Bangkok.
Thank You for reply