Q: iCloud has been messing up since iOS9 update-

Ever since updating to iOS9, my phone keeps asking me to verify my apple ID or something and when I go to it, it says "If you are signing in to iCloud on another device or at iCloud.com, you can get a verification code while offline." and then gives me the option to get a verification code, but I have NO idea where to even put the verification code at and without doing so, it won't let me access my iCloud account on my phone. It ALSO has my mom's email as the email for iCloud on my phone, but I know that MY email is the primary email. I was ONCE able to get into it on my phone, and it wouldn't let me delete the old email address, but I guess something happened and now it won't let me access it AGAIN.

iCloud really confuses me and I have no idea what to do because I feel like I've done every possible thing at this point.

Helppppppp.