Ensure you've also downloaded the latest Google Chrome update, it has various protective and security updates.
Regardless of that, the number one thing you should never do is trust a shady looking site

. If you are unsure of a site, Google (or other search engine) the site for its reputation. Often discussion threads will come up if anyone else had a malicious experience with the site.
Malwarebyes as everyone saying is a great start, but you may want to get an antivirus such as AVG or Microsoft Security Essentials; both have the ability to detect 2 important elements 1. Rootkits, and secondly keyloggers and are a free alternative. Personally, I've used McAfee and I use to pay for it; If I could I would sue them for making me pay for such a shit product.
additionally, type this into a new window:
chrome://chrome/extensions/
Review all extensions here, that you know what they are. If you don't block the immediately and search their credibility. Do note, Google Chrome has no default extensions, so everything there you at somepoint clicked "I agree" to.
Lastly,
navigate to chrome://chrome/settings/ in the url window.
If you haven't already, click show advanced settings and find

Make sure the checkbox "Check server for revocations" is checked.
hope it helps remove the current issue and then protect you from further harm :P again, the best solution is to check shady looking sites.