What do my symptoms show? I've been having irregular sleeping patters (i.e. can't fall asleep, wake up many times, wake up early) get scared very easily, my muscles twitch, my muscles are tight and constantly burn in my shoulders, have short, painful headaches, dry mouth, nausea, anorexia, very tired, cry a lot more than usual, turned off by "fun" things, can get very strange breathing patterns-starting slowing and working up to a very quick pace and then continuing the cycle, cold and clammy hands, think death is an option (which is not like me at all) and have discomfort in my abdomen. I'm usually very upset as well. 
A lot of these sounds like it could be depression but I thought depression might be a lasting thing. I still enjoy life, and find much beauty in it. This week went very well for me, and I was in a positive mood. However, it seems to be short-lived by a few days to a week before I am brought down by this uncomfortable emotion, and it is tiring me so.  I need help to find out what I can fix.

Summarized question: What can cause irregular sleeping, getting scared easily, muscle tightness, burning in shoulders, headaches, dry mouth, nausea, anorexia, fatigue, and not feeling well?