My question is why getting early ejaculation when meeting a woman for the first time ?

Here are some ...: Doing something with someone for the first time represents stepping in a new environ to explore something unknown & uncertain in life, through which you're mentally peppered with up and down ebbs or flying dusts of anxiety, curiosity, & excitement, expectedly affecting your concentration required for adequate performance; some will result in "premature" ejaculation. So, you're "normal" like many.