Coping with being tired

Ok, it’s all going ok. I’ve studied Monday hour 1, I’ve worked out how to get results, I’m getting things done. I also work in, currently, three other jobs, and have a family and am a single parent so I have quite a lot going on.
It’s got to week three and I’m really tired! Not when I wake up. But from around lunch time.
The thing is I’ve been here before. I get tired so I adjust what I’m doing, but then I don’t end up launching my business properly and get stuck in not launching. So I’m trying to ramp up and get to launch and business operating and sales being made.
How do I cope with the tiredness though? I’m getting up early to get work done, my focus time, as I’m best in the morning. But I’m also working through to 10pm to get some more hours in at the end of the day.
I am so tired though. Do you think I’ll just get used to it? I’ll be tired this week and then by next week I’ll suddenly feel much better? What do you think?