Any insight will help

Betty

So i had a blood test done tuesday cuz i had some cramping so i went ro the ER and i was 4 weeks and 6 days pregnant and my HCG level was at 395, the doctor said thats low, Then i had to have an ultrasound done because they wanted to verify my pregnancy but they didnt see anything

Is it possible it was too early to see anything??

But i saw my PCP today and she said that the HCG level was normal so she said it was fine just wanna get it rechecked won't find out the results until monday, so now im worried. I have never miscarried and the ultrasound didnt pick up anything abt a tubal pregnancy. So what is going on im freaking out.