Someone tried to get into my account

That was a good thing to do. Having done so you'll have much better security and never have to bother with security questions in any way. Do you think you account was compromised in some way? See See If you think your Apple ID has been compromised https://support.apple.com/en-us/HT204145.

Have you changed your Apple ID password?

See Change your Apple ID password https://support.apple.com/en-us/HT201355

And see What to do after you change your Apple ID or password https://support.apple.com/en-us/HT204071

Not if you are using two-factor authentication. Have you checked using the instructions in this link? Your Apple ID device list https://support.apple.com/en-us/HT205064 

Great. Can I help in any other way?

Heaven forbid. Be safe.