Do you think my computer may have been hacked? What can I do to fix it?

Yesterday I noticed that the bug “Heartbleed” appeared on my anti-virus icon, but I’m not sure if it’s the actual virus. And today, I changed my Google acount password for Youtube, but after I logout, I’m unable to sign back in. However, I can still change my password each time and gain acces to my channel. But if I sign out, I can’t log back in again. What do you think is the problem?