Energy levels bottomed out

#1

Hi Guys
Just after some ideas. Have been keto for a few months. Was low carb prior so didn’t hugely suffer from keto flu. Have had awesome energy levels up until about a week ago.
I do IF- eating 8/16 from 6am-2pm but if I’m feeling hungry outside of this window I eat.
Im a 35F 5’3 53kgs(117pounds), just had a body scan done and sitting at 16% body fat. Consuming roughly 2000-2500cals. 75%fat
I train 7 days a week combo of weights and LSD cardio. Have been doing this for ages.
In the last week I have had a major drop in energy levels. Getting through a gym session is difficult and it’s not at the same intensity. When I get home I am so tired I need to go back to bed. I have 4 children and even in the midst of crazy sleep deprivation when they were babies and I was doing night feeds, I have never had to do this ever! My energy levels seem to pick up mid morning. I train fasted but always have.
Nothing diet wise or training has changed. Any ideas what could be going on?
Other people in the house have been unwell, could the drop in energy potentially be my body fighting off whatever it is?
Just really hoping it passes and I go back to my usually awesome energy levels.