Keep testing???

I had a miscarriage last February now I’m prego again and I’m trying not to worry about it happening again but can’t help it. I made a doc appt but my appt is not until June 11th. Do anyone have any knowledge to pass along that would help me monitor my pregnancy until my doc appt? And why do ppl say keep taking a prego test? What exactly am I looking for beside it being positive? Thanks in advance