My wife drank a lot of alcohol 1 st month of pregnancy. i am really worried if everything will b fine. this was the only time she had alcohol in life?

Yes: This is common and typically doesn't affect pregnancy at this early stage. Most important is that she identified that she was pregnant and i'm sure is taking appropriate steps to ensure the health of herself and the developing embryo/fetus. You didn't quantify what 'a lot' was, so difficult to answer specifically. For some women that would be 5 drinks in one setting, for others, that could be 2.