Miscarriage or new pregnancy?

So I found out on Christmas that I was pregnant. 😪 Unfortunately, I lost the baby around the 16th of Jan. My levels never made it past 575. I went back for betas on the 20th of January and they had fallen to 137. I was due to go back to the doctor this tuesday coming just for a checkup. I figured by now my level would have reached 0 given in 4 days it fell so quickly. Not to mention my first miscarriage had reached 0 in a week. So I took a test this morning to see if it was still showing positive and there was still a vvvfl. My question is, is this just lingering hcg from the miscarriage or is it possible to have a back to back pregnancy after miscarriage?