Line darkness?!?!!!

Hey ladies I just got my positive this past Saturday! Yay!!!!!! Well I was about a week and 2 days late and according to glow I am 6 weeks 3 days. This is the pregnancy test I took. Before the urine even finished going over the test window there was a strong line this was only after 5 minutes. My SOs grandmother is an identical twin. So my question is is it normal for a line to be this dark and show up so quickly? Or could this be a possibility of twins with so much hcg in my system?????