Nothing showing at 5w3d ultrasound? Any light?

Selina

So long story short had an ectopic in April this year found out I was pregnant again went to the bathroom yesterday saw what I thought was a bit of blood but now not too sure as it was so so light may have been discoloration, went for a transvaginal scan and they couldn’t see anything at all only maybe a sac but not fully sure, my hcg was at 15.9 on 17/7 and yesterday was 4500 29/7 they want to admit me to hospital and I just know they want to treat me for another ectopic, I have no symptoms whatsoever only light twinges in my lower right abdomen. I want to hold on and see how things go maybe something will show next week or that but don’t want to be holding onto hope if there is none, can anyone please shed some light or hope for me? Last period was the 21/6 and doctor says that I am 5w3d, any advise please ladies??