OK, I think I see what is happening here - (I think!)
So it appears you have the same ID used for your FLARM and for PilotAware.
PilotAware will not see the direct broadcast from your FLARM, and your FLARM (via FLARM-in) will not report itself, so that rules out anything there.
I am guessing that you were within rang of an OGN-R station which was capturing your FLARM, and rebroadcasting it to all PilotAware's, this was then picked up by PilotAware, which is why it appears in the display, it was also picking up your transponder.
This is actually correct behavior I think (for the traffic table), but I need to check - this was a requirement for the LAA/BMAA sign-off procedure to get a screen grab.
Now to the crux, this data should NOT be forwarded to any traffic device, or displayed on the PilotAware RADAR screen.
It should be filtered when compared to your own ID
Is this the case ?
Or did you see your own aircraft on a navigation device ?
I can easily check if you have your .trk file for when this was displayed, a search for your registration or ICAO number will clear up any ambiguity
Now there may be a bug here regarding the reporting of your own aircraft on the traffic screen, it could be that the transponder is filtered (when in isolation) but the rebroadcast of the FLARM is leaking through to the traffic screen, I think I need to check that for sure
Thx
Lee