GCSE Maths grade boundaries? REALLY SCARED?

Basically I do Edexcel Modular Maths. For the past 2 units i've got high a*'s for all the exams. But on monday and friday I didn't feel confident in the exams and everyone found them hard. I'd say I got 44-48/60 for each of the exams (thats me being harsh by the way). How badly will this affect my grade considering I got a*'s for the rest of the units and everyone founds these exams this week hard? I'm so scared because I felt I really deserved an a*!