Possibly pregnant

Kai

So 3 weeks ago my bf and I were having sex. Out of nowhere he pulled out and said "i cant tell if I came or not." I turn around and theres cum on his penis. Now my period is 2 days late. Do you think I could be pregnant? How long should I wait to test?

Im worried bc I miscarried our twin boys about 6 weeks ago and I dont want that to happen again.