HELP! MY MUM KNOWS

So I'm 16 and have been in a long distance relationship for 8 months with my boyfriend (Phil) At Christmas I flew to see him and my mum told me no sex, thinking I was still a virgin (even though I lost it to phil in the summer). So the other day my older sister told my mum that me and phil had sex....mum told me she knew (when I was on FaceTime to Phil!). She didn't seem mad but didn't seem joyful. I asked if we could talk about it later and she said yes. So... WHAT DO I DO!?😩😩😩😩😩😩😩😩😩