Not all people experience withdrawal symptoms (I didn't) and different people experience different levels of withdrawal and different types of symptoms. Some people might get headaches and feel very low on energy for a few days. Others may find themselves quite irritable and still others just might feel a little blah for a couple of days. My DH was so cranky on day 3, I offered to get him a tire to gnaw on and had to remind him that while his daughters would be considered low carb, they weren't part of the menu so he needed to stop trying to bite their heads off (not literally, of course!).
The good news is that it does pass, usually by the 4th or 5th day for most folks, so hang in there. Once your body gets through the detox process and switches over to burning ketones for fuel instead of glucose, you really will feel a lot better.