It's like my body physically feels unmotivated...

I've been feeling a lack of motivation for two days now. It's not just in my mind, though. It's like my body physically feels unmotivated, if that's even possible. I've had to force myself to do the workouts, and that I'm currently doing the five day challenge to burn fat and build lean muscle doesn't help. Those workouts are kind of long, and they involve HIIT.

I'm not really sure how to deal with this. I have this tendency to either force myself to go all in, or to give up and think I've failed. I know that's not a good thing. I'm working on it. But for right now I don't know if it's best to just push through this or to listen to my body and maybe cancel my workouts for this week and take it easy and get back into it again next week. I haven't been sleeping well the last couple of nights and I'm feeling it. Usually I'll feel better when I get to sleep it off, but I could be coming down with something too. I just don't know. I can get slight symptoms of having a cold when I'm tired enough, so it's hard to tell which one it is.

What would you recommend for me to do? How do you handle situations like this one?