Not feeling hungry is part of ketosis.
Not everybody gets side effects.
If you cut down on carbs and upped your water prior to starting you may be just fine.
However, day 3 was the day I felt the worst, I had a headache and felt a bit rough.
I was too bad on days 1 and 2. Day 3 it hit me, and by the start of day 4 I was in ketosis - so I was fine from therein. Week 3 was a low time though - felt like I couldn't move a muscle as I felt I had no energy - soon passed though!