PFsense + Ntopng -> Grafana

[yeleek]

Hi,
I've configured PFsense and Ntopng to use the Grafana backend (Influxdb). Metrics are going through fine and I am now trying to create a piechart of devices and the amount of bytes received in the last 'x' minutes.

However even when in table form, I'm getting the entire amount of bytes_received not that in the last 5 seconds (or other time period). What am i doing wrong please? Query is here:
link
Thanks in advance