I'm scared I might be pregnant, I don't know what to do right now

Mary • Vegan/Vegetarian. Cat lover.
So I had sex a week or two ago and while we were having sex I started bleeding, but I'm not virgin so I didn't understand why I would bleed. I know I might be like worrying for nothing but it's in my nature. So now I missed my period and I'm scared it might be something more....