I lost my virginity to my ex when we were both 17 and both virgins. We had been together for two weeks which isn't really very long. We had been friends for quite a while and I don't regret my decision in the slightest. We went on to be together for four and a half years. You know when it is right and for me it was after two weeks.
We were both 18, and it was just under 2 weeks after we'd started going out. We'd known each other for about a month beforehand. Neither of us attached much importance to virginity and we didn't worry about 'waiting until it was right' - there was no reason not to, basically. Neither of us regretted not waiting longer.