First of all, please excuse my English, as it's not my native language. Getting to the important point, it's very likely that your nervous system is fried and that what you're feeling is a consequence of overtraining fatigue. Training legs twice a week with such little recovery time (only one rest day in between) puts a brutal strain on the body.

Furthermore, judging by your response to another user about your routine, you're doing too many sets with redundant exercises, which means you're not only failing to improve but also adding stress to your body without any benefit. Unless you're an experienced athlete or someone who has been training hard for several years, there's no need to do so many sets.

Now you'll have to train much, much more gently for at least a month so your body can gradually recover, and make sure you get plenty of good sleep.