Pregnantcy scare help please ):?

Hi, I'm a 16,almost 17 year old girl. I'm having a pregnantcy scare . Me and my boyfriend had sex without a condom but he pulled out and finished himself off . Now I havent gotten my pierod . But I usually get it a week or so before the 29th. Now the trick is that I don't get my pierod every month it just comes whenever . I'm scared I might be pregnant . Im having no sighns of my pierod coming . Soo I'm nervous ): if in pregnant my whole lifes gone . My parents would kill me . I don't think I could do it ): anyhelp from anyone would be greatly appreciated . Thank you .