I have been taking the birth control Yaz for about a year. I had my last period on April 2nd (first day of period) and I was supposed to take the new pack on the 3rd. However, I waited a week and started taking it again on the 10th. I had unprotected sex on the 13th. Could I be pregnant? If so, when will I be able to tell and what would the earliest signs be?

ANY time you have penile insertion you run the risk of pregnancy. You can limit that risk, but not eliminate it.

So you could be pregnant. You will have to wait until you miss your next period to take a test.

There's always a chance of pregnancy, even when you're taking birth control properly. The fact that you waited to start your next pack means that you've put yourself at a higher risk of pregnancy.

There are many signs and symptoms of pregnancy, but they're very general, and the majority of those symptoms are also symptoms of PMS. Many women never experience any symptoms other than a missed period, and some women don't even experience that (bleeding in pregnancy is possible, and often mistaken as a period).

You'll have to wait until your next period is due. If you miss it, then test.

If you're trying to conceive (and it seems like you are), then I have to ask why you're even bothering with birth control?

If you're not trying to conceive, then why are you misusing your birth control and increasing the risk of pregnancy?