Dr Dre - I Need A Doctor chords

Capo 5 to be in key with the song, but I play it on 4.
[ Tab from: http://www.guitaretab.com/d/dr-dre/279739.html ]
Dm                    Bb
I'm about to lose my mind
                         C
You've been gone for so long
C (keep strumming)
I'm running out of time
         Dm
I need a doctor
          Bb
Call me a doctor
           A
I need a doctor, doctor
       (stop strumming)
To bring me back to life


The rest of the song is Dm Bb C(for 2 measures) Dm Bb A (for 2 measures)