4wks+4days (estimate) looking for advice

So. I’m currently a little on the panicky side because I’ve taken 3 test so far since the day I kinda assumed I was pregnant and so far they’ve all been saying the same thing.

Pregnant, 2-3 weeks (was conception)

But I’m very paranoid because this is my second pregnancy as my first one was a miscarriage

Where is it so soon to figure it out. (Only 4 weeks, one week late for my period) is it still possible I might not actually be pregnant? I know it might sound silly but I’m very new to this and have no knowledge what so ever.