The headaches may also be a sign that your fuel reserves are low. especially in the early days, when your body is still using up the last remnants of glucose/glycogen reserves, and switching into full ketosis mode. EAT SOME PROTEIN. It's wise to eat a small meal or snack containing protein every couple of hours or so.

Not sure what you have for lunch, a lot of folks have a small salad and a piece of chicken, or a bunless burger, then go for 6 hours till supper time. Way too long. If you're at work, take some of those cheese strings, or beef jerky strips, a handful of nuts, or a hard-boiled egg (leave in the shell).

And drink lots of water or other carb-free liquid to keep those ketones flushed out .. .. and coffee is NOT carb-free. An 8 oz cup has 1.1 carbs (black), plus any cream and/or sweetener...

take care, keep us posted of your progress

Doreen