am I covered under the 72 hour visa free transit

my gf is american and I am canadian, all our flights are booked but on separate airlines (but I have documentation) we are arriving in beijing from toronto March 23 and leaving beijing onto bangkok march 25. which we plan on checking into hotel and sightseeing in beijing. am I covered under the 72 hour free transit?? on the return flight home we connect in shanghai and beijing but it is under 24 hours and we will not be leaving airports during this time.