Microsoft windows security alert. porn alert pop ups

 I have Norton 360 premium installed, but Norton are having problems with support service at this time.

I was on news page and  clicked on a farming blog featuring a picture of a tractor and a full, blue background page popped up with: Microsoft windows security alert then a couple of smaller alerts mentioning porn alert.

I quickly pressed the X, close page signal, but am worried, as on line blogs say it is a trojan virus.

Any help appreciated