Don't you ever maintain several projects at the same time

I'm currently a member of this projects:

• IT company and Uni cooperation as a QA engineer of distributed server-client java game and this is hell. I'm not close with Java at all and also I had to learn SO MANY FRAMEWORKS, like osgi implementation called Apache Karaf, JUnit, Apache JMeter, Jenkins CI server, Mockito mocking framework and so on. RAPID LEARNING as it is. And so agile.
• Another IT company and Uni cooperation program called Lab as a member of clipboard sharing crossplatform app. This required learning of network communication and TCP/IP stack and Qt.
• Chair ordered me a huge and scary server-client web project to compute uni rating. Spring, DAO, Liquibase, MyBatis, REST, Javascript, tomcat and so on.
• My operation systems course project. I cannot even describe, how complicated it is. bash generator, pure C89 code, graph search, fcntl. I wanted to make shared memory here, but I just have no time.
• Social networks online correlations python script (I left it).

Too much. 

And Outreach Program start is soon. I'm so exited, but I'm too tired to write sth now. Wait for a post later, but before 9th December.

Don't you ever maintain several projects at the same time.

Never ever again.

P. S.
I just had my laboratory work done, overloading operators for huge class system. Why have I done this? This wasn't in the requirements. Because I JUST CAN'T KEEP IT SIMPLE. But you should.
P. P. S. And if someday you would find the idea of splitting to several task attrative, just remeber that
I ended up coding 24/7, sleeping less then 6 hours per day, losing advanced stipend at Uni, could not take a breath, most of time depressed or crying, procrastinating and having my head aching.