Most Helpful Girl
I honestly don't believe this question has an answer. I think it differs it could be within a few days, a few feeks, months or years. In this day an age you contact them 24/7 via social media and messaging apps so realistically it happens much sooner than in the past.
I do however believe that age will change how quickly you fall in love and how previous relationships have gone etc. But there is not right or wrong answer.
I myself say in previous relationships take about 6 months or shorter :)
Most Helpful Guy
If you're not feeling it already that's not a good sign. When you get more comfortable with someone not really a time frame but mutual state of understanding.