So what you're telling this girl is that birth control pills caused infertility? Come on now! Please don't give out incorrect information with something you know nothing about.
Evanescentsoul, get a pregnancy test and see what's up. If it says negative wait a few days to a week and take it again. All birth control pills make your periods shorter so perhaps Yaz is too strong/weak for you. It depends. I was on 4 different brands until I found one that worked. It's going to be ok.
Yes, the first thing is to test for pregnancy. I have children older than you, so I feel very compassionatly toward your well being. I understand it's difficult to be 18, firtile, and in love, while not wanting a baby. It sounds like a frighteningly complex responsibility turning your love life into a science project with the use of a drug on your young body. What concerns me is the long term effects this drug will have on your future firtility. In other words, I have many friends my age, 39, and younger who cannot get pregnant and have the baby they dream of because at your age they began drug-birth control, and continued for several years. It's a heartbreaking feeling when you do choose to have a baby and cannot. When I was your age, I married, and successfully avoided unplanned babies by foam, and other temporary over-the-counter methods, as well as enjoying the first 2 and 3 days before and after my menstruation. I'm not familiar with the latest methods, but I'm sure internal-drug-type methods are hazardous to your future happiness and health. You can ask me questions any time, kiddo.