I need help. Will I get pregnant?

Okay so I was recently switched from Yasmin (taken it for a year) to Alese. I was switched because my blood pressure is a little high and the doctor thinks it may have been my birth control. I was just wondering if there is a period between switching pills where you should be more cautious during . Like how when you first start taking them you need to be careful for a month or two, is it the same when switching? Thank you!