**Neither a teacher nor a native speaker.**
1. Sounds okay to me.
2. Sounds not okay to me.
3. Sounds strange to me.
Some more details:
Number 2 would be correct, if you were talking about the present.
She told me that if we lived 3 three months together, she would check if I come back home early everyday.
I think this sentence is correct, but its meaning is completely different.
Number 3 just sounds strange, I do not see the sense of use in that sentence.
I hope some other members will say something too.