feeling overwhelmed/sad?

Long story short, adulting has be stressing. I haven't been able to get a good nights sleep, I've been experiencing migraines more frequently, and my neck and shoulders are killing me (I'm 22 btw). So I work 3 jobs and go to school full time as a STEM major. I am guilty of being a workaholic and I'm usually able to handle everything, but lately I've been feeling a little down. I know I put a lot of stress on myself, but I feel so blah!! I also got my period which isn't really helping with my emotions. What do you guys do when you're feeling down? I know things always end up working out, but as of right now I'm so tired and can't really sleep well and my muscles are so tense it hurts.