Hi,
Welcome to Microsoft Community.
You can check the recent activity , which will let you know IP information, from where you have logged in.
You can check this link: https://account.live.com/activity
You can also protect your account from hackers. I suggest you to enable two steps verification.
You can check this link below:
http://windows.microsoft.com/en-us/windows/two-step-verification-faq
You can also check this link below for more information.
http://windows.microsoft.com/en-US/windows/outlook/hacked-account
If you need any further assistance, you can contact customer support team, you will find the details in the above link.
Thank you.