forgot what email address my icloud was based on
Hi,
i forgot my icloud email address my phone currently is linked to. i have been using this phone since months and never logged into icloud. i don't even remember when i activated icloud on it. now a few days ago, i removed sim card i have using since months and inserted another sim card to call someone. iphone started asking for activation. it is showing a******@gmail.com text. i have an email starting with this letter but when i logged into it, it is showing no devices linked to it. what should i do? is there a way to know the complete email the phone is linked to? please help.. this phone is useless for me.. i am able to receive calls on old sim but no outgoing.
iPhone 4S, iOS 8.1