Overwhelming but Much Needed Socialization

Today was a somewhat crazy day.. well, it has been a crazy week honestly. I have been really struggling to stay on track, be productive, motivated, and getting my shit done. I'll try to summarize the cycle I seem to find myself stuck in often.

1. Make a list or think of all the things I need to "get done" (Not really considering deadlines much or priority/importance)
2. Get overwhelmed thinking of all the things I need to do and how easy I could fail, or what if I don't do it well?
3. Sit there for way too long contemplating things, don't realize how much time has gone by. It's like I'm so paralyzed in thought and overwhelming that all I can think of doing is laying down. I get physically exhausted just thinking about -everything-
4. Feel more stressed and guilty for not getting my shit done and just wasting time sitting there frustrated. I really have a difficult time getting myself to just ACT instead of getting caught up in the "kajs;dfkajs;dkfja" of my brain.
5. Be depressed because I know I could have done better than I did.. or am. Then I feel shitty about myself and confirm my 'beliefs' that I'm just pretending to be smart and helpful but really I'm a shitty, mean, loser.

WHY AM I LIKE THIS?

All I really NEED to do is pick the hardest thing and START on it! Then, everything else is easy once I get the motivation going. My schedule always seems to get thrown off somehow though.