It really depends on how your body copes with a fast, so if it is your first it's very hard to predict. Fasting can bring extra energy, clarity and strength or it can leave us bedridden, either extreme is possible and often there is a mixture of both. It would be a good idea to plan for both.
A general rule of thumb appears to be that the more unnatural your diet has been the worse the symptoms you can expect while fasting. There are no hard and fast (no pun intended) rules though. My advice would be to reduce your workload but leave the possibility there of doing more if you have the energy. Though I'd say preparing for your wedding will keep you quite busy enough! :)