Breaking down your tasks into smaller chunks makes them feel more manageable. While things feel so overwhelming perhaps you can take a short break to listen to music and get something to eat. Then go back at it for 5 minutes. Look out the window. Work another 5 minutes.

You sound like you are working hard - are you eating nutritious foods and sleeping enough?

Bouts of other illness (colds, flus, esp. stomach flus) trigger mood episodes in me too.

You can get through this! Academic pressures are very challenging for everyone who attends school.