Have you ever been working out and you feel some weird pain? Maybe it's your knee bothering you or your shoulder, it feels weird, but you HAVE to finish your workout. The thought process of "let me just finish this exercise" or "let me just finish this workout" is what leads us to end up with more pain and more injuries.
I have been there many times, more so in my 20s, where I would feel something funny in my foot or shoulder and I would just think: I just need to finish this workout, I will take off tomorrow. If only I had stopped my workout or at least stopped working out that area that felt suspicious, my recovery time would have been better.
Now, that's not to say every little muscle soreness means something, it's when you feel something irregular and you ignore it. It's that nagging voice in your head that says, "you should stop!" Listen to that voice and if an exercise doesn't feel right or you feel weird pain when working out, then stop!
I want you to push yourself and get stronger and leaner, if those are your goals, and muscle fatigue comes with those goals. Make sure to differentiate between the two, muscle pain versus muscle fatigue. Fatigue the heck out of your muscles, but don't workout when you have nagging pain. I've so learned and maybe you have too, it's not worth "pushing through the pain" if something doesn't feel normal, give it a rest and try it again another day!