Eating after sehri ends

Q: I woke up this morning and drank water after fajr. Not realizing I needed to fast today. However, since then I haven't eaten or drank and want to keep my fast. Would it be accepted? I didn't know I had to fast today and a friend told me. 

Pronouncing few words incorrectly in salaah

Q:

1. I recited ‘saliheen’ with a bottom throat ‘ha’ and noticed during the middle of reciting it during the enlongation of the last syllable. During the elongation of ‘heen’, even after I realised, I still pronounced it with my lower throat. Is this considered intentionally reciting something wrong and did it invalidate my prayer?

2. During the du’a portion of Witr, I usually recite Rabbana Atina Fidunya 3 times. The second time I recited it, it felt like I had recited ‘Rabbana atina fidunya hasanatan wa qina adhabanar’ as opposed to the correct full invocation. Because of my uncertainty, can I assume my prayer is sound?

The meaning of Haneef

Q: I know the Holy Prophet was the follower of Hanif religion before prophethood. Is it correct that the Hanif religion was not corrupted before Islam and when Islam came, the Shariat of Hanif religion was abrogated? Also did the Holy Prophet knew of Hazrat Ibrahim AS before prophethood?