scared

So I recently found out I was pregnant I have been having alot of pain in my lower left quadrant. I went to the hospital and they told me I was five weeks , I was fine and sent me home . I went to a different hospital for a second opinion and found out I have a cyst on my left ovary, and I'm indeed 14 weeks along . when they did the ultra sound they found a sac but no baby or anything that appears to be a baby . My hormones are still going up and I now have to have them checked every two days , I go in for another ultrasound next week but I'm so scred why wouldn't they be able to see a baby that's the size of a lemon ?