Sorry to hear you are having the dreaded headaches we all hate. They really are horrible aren't they?
Other than what you are doing (extra water and paracetamol) the only other thing I can suggest is sleep. After a few early nights, ketosis will kick in and you'll certainly feel on top of the world!!
Hang in there, at least it is one of the signals of ketosis which is a positive thing!! I use ibuprofen which gets rid of the headaches so if paracetamol is not working well and Ibupfoen is OK for you you may want to give it s try. Weigh in will make it worth it!!