Can a cyst resemble a early gestational sac?

[kiddo0820]

I had a couple positive HPT but and went to the doctor to confirm it and because I started spotting the doctor did a urine test that came back negative, he sent me for an ultrasound to make sure I wasn't pregnant and he said I am possibly pregnant because there was a small fluid filled sac in my lower uterus that could be a gestational sac but it might be a cyst. I go in tomorrow for blood work to check my HCG levels and I am so scared that it's going to come back negative. I was just wondering if anyone thinks that I'm pregnant or if it's just a cyst.

I also forgot to add that my last period was 12/16/09 and I have been having pregnancy symptoms!

[lilianasmom1116]

a lot of times the doctors urine tests arent as sensitive as others we can buy. so it just may not have shown up on his. OR is there any chance you could have had an evap line??