I passed my viva with minor amendments. This was about half a days work and I have now submitted this. Does anyone know of normal timescale for this to be approved/ rejected and how often these changes are rejected? Feeling quite anxious about this (probably shouldn’t)

Sounds like you're bragging, lol! Congratulations, HopefullyDr! Half a days work is amazing, and don't worry, the changes won't be rejected. I don't know about the timeframe, but I think it is safe to say that you can go celebrate now.

Its odd- I have done all the celebrating, but now my PhD related anxiety has crept back in and starting to worry about the what ifs! I guess this is just part of the PhD process (hopefully the last part!). Do they ever get rejected?

Having corrections rejected does happen but I am not aware of anyone with minors having an issue. I wouldn't worry about this at all. I think it took about a week or so for me to get my corrections approved and it was all done by my internal examiner. Once the external is happy you should be home and dry.