Usually that indicated your modem is having a hard time keeping signal lock with you satellite beam...usually seen during weather related events or because dish has been slightly moved from center alignment with the satellite.
It can also be caused by growth of trees or other things (bushes, hedges, etc) that are partly blocking line-of-sight to the satellite. These pings you're seeing does not count on your usage totals...at least they have never counted on my usage..
Go here and log in, then look carefully at any warning or non-green indicators:
The blinking lights you notice could just be your modem pick up and sending signal, this is not out the ordinary, may not be a serious issue. Feel free to send us your account and contact info to email@example.com