How will I know I am in Ketosis?

Hi, been doing SS for 3 days. Managing fairly well but, how will I know when I am in Ketosis?

classic signs are furry tongue , nasty breath , feeling cold , a return of energy , and a reduce in physical hunger . If you have stuck to SS 100 % you WILL be in ketosis by day 5 , the only definate way of telling is using ketostix ( which you can get at chemist ) but you really dont need to as you cant not be in ketosis if you are 100 %

Hi.
I am on day 6. I have all of those but I still lack in the energy dept. Is that normal. Will it come back soon.