I have face this kind of situation few times and All I do is give myself a break. Then, I tend to tell myself that I can't stay like this for a long time, I have a lot of responsibility to work on (reality hits, adulting sucks). Last but not least, before I turn myself back to be "on the track" again, I usually go alone, have a me time, and look for a new atmosphere. These all works very well on me.