When to schedule Doctor visit?

Ge
I just got out BFP few days ago. According to this app I am 3weeks 5days pregnant. My PCP is out of the country for a week....
Question:
1. DO I FIND AND SCHEDULE AN APPOINTMENT WITH A OBGYN? 
2.DOES MY PCP HAVE TO REFER ME?
3. WHEN DO YOU SEE THE OBGYN AND WHEN CAN YOU DO A LAB TEST TO BE ABSOLUTELY SURE YOU ARE PREGNANT?
thank you,
Still a but in denial 🙈