What do you think?...

I had a sonogram at 5w3d and the tech saw two sacs in my uterus. She had me come back at 7w2d because the previous ultrasound didn't show anything because it was so soon in my pregnancy. Well I had my 7w2d ultrasound and there was still two separate sacs in my uterus but the tech said I was only having a singleton pregnancy. Has anyone experienced this before? Here is a pic of my latest ultrasound.