When your body is fighting increased inflammation, you are experiencing malabsorption and possibly anemia, it is not that strange to think you are tired. When I was a few weeks away from surgery I would sleep 9 hours a night, and still wake up quite tired. I had no energy most of the day.
Ensure that you are eating nutritious food (even though you may not absorb everything too well) and drinking a lot. Also you may need to take iron pills if you have anemia (are you bleeding at all? blood loss would cause this). This is something a blood test and diagnosis from your doctor would tell you. You can take iron over the counter, but I think it can be dangerous so speak to your doctor about it.
Do not stress and realize that you need to let your body rest so that it can fight the good fight inside you.