Need to gain mental composure

Slept abysmally last night because I attempted to go to bed at normal bedtime hours because I had work early today.  It was absolute chaos as today was the first day of spring basketball but my work performance was good despite poor sleep. Where it caught up was after my shift...was so exhausted I just crashed for 3 hours.  Consequently I didn't get any school work done...I'm behind with school work and spring break is over.  I can't be thinking that way but I'm mentally pretty done with school at this point.  I know my plan was to major in nutrition but I regret taking nutrition classes simultaneously with my major(Parks recreation and tourism).  I enjoy nutrition but its going way to fast paced and I'm having to put lots of effort into it when it should be mostly about my major.  I have another stupid nutrition test  coming up and I'm behind like I said...I really need to find a way to finish at least OKAY.  What I had been doing is a bit unreasonable but I just need to get through with this semester...NO MORE NUTRITION classes untill a different point in time!