Adult ADD, Brain tumors, or Psych?

[discovermyproblem]

I have the following symptoms:
1) difficulty concentrating (especially during boring or repetitive tasks)
2) I have trouble remembering my phone, car keys, to lock the door etc.
3) I have a hard time memorizing anything or remember I have to complete a task
4) I have trouble beginning anything and finishing it off properly.
5) I go through life as if it were a dream, and I have limited control over my decisions.
6) I can't spell words correctly as I used to.
7) I usually leave many letters out of words, or words out of sentences.
8) I make many careless errors on exams.
9) I have been nauseous for weeks at a time (on and off) especially in the morning.
10) I feel disoriented all the time.

I'm a 20 year old female, 120 lbs, no history of medical problems. Please help me figure out what the problem is. I'm a med student, and this problem is taking a toll on my grades and social life.

[discovermyproblem]

Does anyone have any suggestions as to what might be wrong?