Using Outlook for iOS in business environments for email and scheduling
How can I be sure that my account was not hacked?
I got 1 simple answer for you, if your mailbox is hacked, they will kick you out and make sure you can't get back in. Trust me on this. They will not ask you to send them money. They can do more damage by scouring your mailbox for things to steal (reset your bank account passwords etc). Then they'll phish all your contacts.
Those idiots can't hack. Period.