Security Risk

I think my platform is compromised from a security prospective.

1. I am getting a crazy number of new users that show as “subscribers” in the users section even though I have that option disabled.
2. I just noticed injected text in one of my pages: http://www.jamaln.com/category/tutorials/tips-tricks/

!!! Can you please advice asap on how to remove the injected text and how to stop the unauthorised registrations.

The blog I need help with is http://www.jamaln.com.