I had sex a week before my period and a first day of my period then I had a normal period, then after 3 weeks I had unprotected sex 4 days before my next period with a different person which I missed now for 4 days so am I pregnant for the last or 1st person. Please help am confused. I tested positive

You're four days late and tested positive?

An ultrasound will give you an idea as to how far along you are, but really, there's no way to tell you who the father is without a DNA test. You'll have to wait until the baby is born.