Do you know how to do the CTRL/ALT/DEL combo buttons to open the task manager?

then click on processes to see what is running on the system?

then if anything looks overly suspicious google that process name to see what it might be.

this is a safe link for looking up processes-
http://www.processlibrary.com/

If the AV is showing as running and you recognize the name - you can end that operation by highlighting and clicking the End Process button at the bottom of the task manager page.

I'll check back later -working on the barn project...before rains hit