High ketones

Hello. So, I finally checked my ketones with a urine stick and they were 8.0 mmol/L my BG, however, is 5.8 mmol/L. I'm guessing I only need to worry if my BG is high too? Just wasn't expecting my ketones to be so high. I did fast for 16 hour last night until this afternoon. Just want to make sure am doing things right, any advice would be greatly appreciated