I use and believe in Malware Bytes. I recommend you download and install it on your computer, then run a scan. Malware Bytes allows you to use it free for 14 days. During those 14 days, it runs in the background to protect you. After the trial period, it no longer runs in the background unless you purchase a subscription - but you can still use it for free. You just need to manually run the scans. It's VERY GOOD at find nefarious software on your PC and quarantining it so it can't cause any damage.
https://www.malwarebytes.com/