[CaptainCastle]

So I had the last two weeks off work because I've had a virus which is taking a long time to recover from. I went back to work yesterday, as I thought I shouldn't have more time off, but I really shouldn't have done. I've decided to be sensible today and not go in.
What I want to know is; as I went back for one day do I need to get another doctor's note as it's for the same illness, or does it not matter because it's only one day? Slightly confused as to how this al works.