Q: my laptop might of been hacked

mac pro ios6 my wife was on fb when all of a sudden all these pages started opening. then a popup from safari popped up with a number to call

said suspicious activity suspected; my wife called the number and the person started asking for info so my wife sounded suspicious to caller and caller hung up.

so we shut down computer. when we start up her side, when we hit safari, the popup  (safari warning with # to call comes up. when I go on to my user side and log on, every thing seems normal. Can  anyone help?