Like I said, check if you are indeed have a 72mbit connection (downloadspeed *8 = connection how the ISP says it). Your router configuration site (192.168.x.x) would be the most reliable source of information for this.
Speedtest would work too, if you hit 72mbit here than there is an application leeching your intarwebs. I seriously doubt a single application is capable of this for a while without your knowledge.
If you have 1mbit (on either speedtest or router), your connection has been changed and you would need to contact your ISP for more information.






