Dear Orlando:
It's a C-minor chord. There no possible doubt about it. Analyze the harmonic progression you have each bar, and the whole harmonic structure of the first four bars and you will notice that. In measure 3, the chord on the second beat is a C7, i.e., a secondary dominant to the subdominant degree (which follows on third beat). So, there is no connection between the function of the C chords of the second and fourth beat: one is dominant, the other is tonic.
It becomes more clear if you make a schenkerian analysis, and notice that basically you have in the first four measures a simple progression of i - VI (- i) - V: the other chords just extend this.
Furthermore, you have an echo of this in the second group of bars (5-8), where in the same metric point you have a c-minor chord.
Best wishes!
P.S.: By the way, the Urtext shows a flat on this particular e.