I have had EC bunnies before. They were severely affected and not able to do anything for themselves at first. For any poorly bunny, it is essential that they continue to eat to keep their guts going. Syringe feeding may be needed for a while. You can either use the prepared powdered food, or mush up their normal pellets in hot water. Often a bit of babyfood fruit puree helps to make it more syringeable. Keep an eye on their output - if the poos are getting smaller and less frequent, they need more food / fibre. Dandelions and fresh grass can also be useful to try.
If they are not mobile, you may have to keep them warmer and clean them up with bum baths.
It is very early days if you had a diagnosis on Wed. I would suggest at least another week and you should see some improvement if it is EC. The full treatment course is 28 days, but it can need additional courses and can be a bit of a rollercoaster with ups and downs. The good news is that EC normally has a good outcome, with even very severe cases having only minor symptoms remaining (often a head tilt).
If there are any other symptoms, ask your vet for advice as there may be more than 'just' EC. You are doing well to get a prompt diagnosis and treatment plan. A lot of the rest depends on your supportive nursing and how your rabbit responds. Sometimes it can seem to be a long, slow recovery and you have to hang on in there if you are both coping. Sometimes they can bounce back within a couple of weeks (but keep the treatment going for the full 28 days to break the lifecycle of the parasite). I used to compare week on week to look for improvements, rather than day to day.
There are some quite detailed threads on here if you do a search on EC, or several good articles online:
http://www.kingswoodvets.co.uk/rabbit-e-cuniculi-illness/4586826046
http://www.houserabbit.co.uk/resources/content/info-sheets/ecuniculi.htm