Ladies I need your advice

So last night I went to the ER because I was having abdominal pain on my left side I told them I had took a pregnancy test & it was positive & I wanted them to see if everything was ok well they did blood work & they did tell me that I am pregnant but my HGC was low & they also did a ultrasound but didn't see any pregnancy I'm scared something happen to my baby on the glow nature app it says I'm 4weeks & 2 days they told me that they didn't see anything on my Fallopian tube or my uterus they said that I might of had a miscarriage or its to early in my pregnancy they also told me that I might have a ectopic pregnancy I'm scared I don't know what to do