Quite so. The first thing to do when something unexpected happens, is to run a complete scan of your system, with your Antivirus. Recommendable is to run Malwarebytes and CCleaner or eq. too.
Hacking is a true problem, fortunately it isn't very common. But if you act in some environment / homegroup concerning work or studies, there's always the possibility someone has stolen what you have done or achieved. That's truly nasty business. Like a saying goes, Keep your friends close but your enemies even closer - I don't really support the idea, because it feeds the enemy, but it's good to think about that aspect. You never know where the frog is, unless it makes a sound or visible jump.