Nikah on phone

when i was 16 i used to talk to a guy on phone. one day he called me on my number and a person which he said was a molvi asked me thrice if I accept him in my marriage and i said yes three times on phone. at that time I was alone, and i dont know anything about the other side of the phone that how many people were present, the speakers of phone were on or off, who was the person who asked me that, i dont know anything. i never signed any nikah nama. i met the guy 2,3 times after this incident but never formed relationship of husband and wife.

i know that whatever i did i wrong and a big sin, i soon repented, and completely stopped talking to that guy, i also started covering my face and started following islam completely.

its been 6 years now and today i am engaged to some one else. but i still doubt that i am in nikah of that guy. I dont know if it was a real nikah or a fake nikah

I want to ask that:
1) if it was a valid nikah?
2) can i marry now someone else without letting anyone know about my past? is it necessary to let my parents and my fiance know about whatever happened in my past?

if you can provide me with a reference of a hadees or qurani verse or any fatwah, it will free me from my suffering.

Ps: please note that i follow hanafi fiqh, so i request you to provide me answer in the light of hanafi school of thought if possible, i also request you to keep this question private

waiting for response.

May ALLAH give you reward.

JazakALLAH khair,
your sister