Order The Pill

I was prescribed a new birth control (Ortho Tri-Cyclen Lo) today but I’m still in the middle of my old birth control pack (Yaz). I want to know if I finish my old pack first before I start my new one or start my new one right away?

My sister started taking birth control and about 2 weeks in, she stopped because they were giving her headaches and causing her moodiness. As it is probably expected, she had a period within 2 days of quitting. Then she had another period in 2 weeks. Will her body naturally reset itself? Or did using birth control mess something up? She doesn’t have health insurance so visiting a doctor is the last option for her.