What's going on ?...

I am a little confused because a couple months ago I had sex for the first time and since then my period has been really really light and lasted like 2 days. Usually it lasts like 3-4 days. Idk what to do since my mom doesn't know and she would kill me if she found out or if I made an appointment. I don't know if this is normal or not or unhealthy. Anyone have any ideas ?