VPNs don't make you anonymous. Your VPN provider will still be able to see your true IP and all your traffic, and there is no way to be 100% sure that your VPN provider isn't keeping logs. If you have paid for your VPN with a traceable form of money (bitcoins which have been linked to your identity or any type of fiat), then you could be complete de-anonymized and have all your internet activity linked to your real identity.

VPNs are great for a variety of reasons, and I use one a lot of the time, but if you want to be anonymous then you need to be looking at Tor.