When I started my NQT year, all the planning folders had 'mysteriously gone missing' over the summer, so I had to do everything from scratch, with no help from my parallel teacher who was a lazy bugger and a mentor who enjoyed knocking me and the other NQTs down. I was well organised and it's the only thing that got me through.
In my first half term, I nearly killed myself by being too OTT with resources and lesson plans etc. By the half term holiday, I realised that if I wanted to have any quality of life then I had to simplify my lessons and stop trying to make every lesson an all singing, all dancing experience.
Do you have a parallel teacher to work with? I would be surprised if you are expected to teach 'proper' lessons this coming week- we tend to do class rules, portraits for display, PSHE activities etc, although our children are only in for Thursday and Friday.
I think you've done the right thing by preparing plans, and at least you'll have a good understanding of where you want the topics to go. If your school has better ideas, then great, but lots of schools still use QCA and they are dry IMO, so new and interesting ideas will be gratefully received.
Good luck with your first week- it's nerve wracking, but you'll be amazed at how quickly it feels natural. My first class were year 4 too, and I really liked them and the year group.