Very confused and need help

I think I’m currently 5 weeks pregnant today. The first day of my last period was December 5/6; however, according to one period tracker app, it was 2 days late but according to this app it was on time. I was supposed to get my period on the 3/4 of this month, but when I was 3 days late, I took 3 tests, all of which came out positive. My period came in December and was normal (normal flow, cramps, etc.). I’m concerned if I could be farther along.