GCSE Mathematics Edexcel

Also that's super easy comparing to changes.

Do you do GCSE or A levels?
And that's pretty hard, although I may be underestimating myself.

No, the Specimen papers are often slightly harder than the actual exam! I found this when I did my Maths GCSE - for some reason, the Specimen papers are that bit harder; perhaps to push you, to make sure you're prepared. But in all honesty, some of the GCSE questions in the exam could be very similar to this. If you understood the majority of it but just found some bits quite advanced and tricky, don't worry. If you felt like you practically couldn't attempt any of these questions, I'd make sure to do a little extra textbook revision. As long as you've understood everything in class and revised, you should be fine! I wouldn't panic.
My best advice for an accurate representation of what the paper could be like would be to look through past papers! The past papers are closer to the real thing than the Specimen paper.
My teachers always said, 'If you can do the Specimen paper, you're doing well!' It has to be said that they are a great way to revise and challenge yourself, and if you do them you can be sure of walking into the exam feeling that bit more confident.
(Speaking from personal experience)
Hope I helped!

Hehe thank you, you were a great help. I will try and attempt this specimen paper, but questions such as "find the prime factors of 132^2", were pretty hard. I was never expected to do something of that sort, since we were always to taught, to do prime factors of just a number, and not a number that can be squared.