Thin endometrium with successful pregnancy??!

I just found out last week that I am pregnant HCG level 14dpo= 97. I went to my OBs office to follow up on an ultrasound I had around time of ovulation and she said my endometrium was only 3mm thick and that I could very well miscarry or have a chemical pregnancy.

I am going for a repeat HCG on wed to see if my levels are rising and if so I’ll have an ultrasound at around 6 weeks.

I am going insane with worry.

Has anyone had a thin uterine lining around time of ovulation and had a successful pregnancy?