When should I kiss my girlfriend?

I'm a freshman in high school, and this is my 3rd girlfriend this year. We've only been dating two weeks now, but I know we're going to be together for a long time. We've seen two movies this week, and have been talking about our first kiss a lot lately. Her family has been telling us to kiss lately, too. Every night before we go to sleep we always do a text emoticon for a kiss (:*). So, I'm kind of scared about doing it, not gonna lie. So, please help me with some advice, like tips or if it's the right time to do it or not. Thanks for any feedback!