I'm freaking out about my exam results!?

I'm getting the results on the 2nd of June (thursday). And I'm freaked out that my results are gonna turn out to be bad. I'm sure to get a B in maths (never happened before). I know that I did very worse this semester. I'm in grade 8. I found physics hard as I had to study a 5 month syllabus in just 2 months. What do you say about that? No one at home believes me. All these things are very new to me. Help Me! How will I cope if I get bad results. When ever I try to forget about the results, something just tends to remind me of it. Help me. I'm kinda feeling very bad.