I am not a psychologist/psychiatrist, so I am not qualified to draw conclusions about emotions and human behaviours, but, looking at the graphs, I believe that we can make some very general observations and match the graph peaks with the relevant events which have happened at the beginning of 2020. I think we should divide the interpretation into two temporal phases: "pre-COVID-19" and the "pandemic time":
Pre-COVID-19 phase (from 1st January 2020 to 20th February 2020) During this phase we can observe some very interesting correspondences between graphs and events:
During the Pandemic (from 21st February 2020) The first COVID-19 patient in Italy introduced a sharp discontinuity into Italians feelings: from the 21st February the graph for fear is constantly high and that for joy constantly low. It is reasonable, but I would like to put the reader's attention on the graph for sadness: from the "DPCM #IoRestoACasa", with peaks and valleys, the trend for this emotion is constantly rising and fear+sadness in Plutchik's emotion classification means 'desperation' and, we can say, 'depression'. Yes, it is again reasonable, but, I think, this is the objective proof that quarantine and segregation are producing bad effect on our fellow citizens, at least up to the end of March. We have to say that also anticipation and trust are quite high and this can be interpreted as a nice level of 'hope'. I hope this was sufficient to avoid heavy states of depression in population. By the beginning of April emotions start being blurred: slightly less fear and sadness. The number of contagions begins to really decrease by the first days of April and people seem to be in a 'suspended, waiting state': no big emotions, waiting for something that should happen soon. By surfing the Net (again I am not an expert in interpreting emotion and in psychology) I found that another interpretation could be possible: emotional numbness, or a general lack of emotion, a state caused by anxiety and depression. A sort of apathy.
After this moment of 'numb', there was two events that generate larege peaks: (a) the Italian Liberation Day, with a lot of Joy and Trust, and (b) the the Phase 2 announcement of the pandemic fight by Conte. This second event generates a large peak for Sadness and large negative peaks for Joy and Surprise. People hoped for less restrictions and the Conte's announcement did not satisfy the expectations. By the way, after the first disappointment, in the following days people restarted to show a nice level of Trust and Anticipation, with a relevant peak of Joy for the Labour Day (1st May). This nice moment of Trust continued for the following days in the beginning of May!
Work in progress! Stay tuned!