Help me out ahh

Shannon
I had protected sex last night, the condom didn't break, but I am not on birth control, But I'm not due my period until next week at some point and I have two questions..
1) what are the chances of me being pregnant? 
2) I can't take the test until the day my period should come, so if it does happen to be positive, is there no way from me preventing it?? 
I'm only 16 and it was my first time so you can under stand why I'm a little scared😓