I cannot access my Microsoft hotmail account and think it’s either hacked or a virus

 I am having to email from my sisters email account as my hotmail account has been blocked. I noticed that there were 3 delivery status notification (failure) emails in my account to email addresses that were familiar but that I had not sent. The attachment is a MIME attachment. I now cannot access my email account *** Email address is removed for privacy *** with my password. 

I tried to verify the account by giving all the information needed to prove that I am the account owner but the security information I gave (which I know is definitely correct!) did not match up. I can only think that a hacker may have already changed this information. I then got an email saying my account has now been blocked. 

I can give further information about some of the emails sent and received to further prove that I am the owner of this account but I really need someone to help me to get my account back. I really can't delete it as I will loose all my contacts etc.

 Please can somebody help me?? 

Many thanks