I have been asked if there is a way that you can receive notification of new pages being created at the site collection level. I know you can set alerts at the page library level, but they want this done at the Site collection level.
You can checkout this earlier discussion if it helps you to resolve your concern – https://social.msdn.microsoft.com/Forums/sharepoint/en-US/5e9eb983-f23b-41e0-9548-12839e4621fb/sharepoint-2010-site-level-notifications?forum=sharepointdevelopmentprevious
I will also suggest you to have a look at this SharePoint auditing tool which should be an ideal solution to work around your situation and get notified for every events in SharePoint server.