Python: How to plot time interval from a Dataframe in Pandas
Some suggested alternative plotting methods to visualise this data:

Histogram of the y-axis. Check the distribution of time intervals
df.plot.hist(by='interval', bins=10) #test varying the bin size

Plot smaller subsets of the data if the order is important e.g.
df[:100].plot() furthermore, if there is periodicity in the data, e.g. daily, hourly etc. you could plot each hour on top of each other (in a different colour) to compare the differences between periods.