Since when am I protected from pregnancy if I took my first Diane-35 tablet 12 days after taking my last Yasmin tablet?

Good morning, I took Yasmin for 5 months, then went to the hospital for tests and diana 35 was prescribed to me. However, I started using it 12 days after the last Yasmin tablet. The doctor told me that in such a system I take without the last four tablets this Diana. Am I protected from pregnancy by diana's first blister? Or am I not fully protected by the fact that I missed 4 tablets this month? Thanks in advance for your reply.