I am taking Levora birth control. Last week I went on vacation and accidentally left my Levora pack in my purse in the trunk of the car two different times. One was for 4 hours and the other for 5 hours. I am concerned that it was quite hot in the trunk (I was in Florida). I didn't think much of it at the time, but now I am worried that the heat could have made the birth control ineffective. The package is not damaged and the pills do not look any different. I have continued to take them as I normally would. How much does heat affect the pill? Should I be worried?