Uterus size/ possible twins??

hid31109

Hello fellow Momma's to be!

I had a question in regards to uterus size. I had my check-up today at 15 weeks and my doctor said my uterus is alot larger then it should be. I am having an ultrasound this coming wednesday and he told me to have the tech check and make sure there is only one baby in there. Has anyone else been told their uterus is larger then normal and had only one baby. I had a ultrasound at 7 weeks (due to excessive m/s) to check how far along I was and confirm only one baby.  We were right on with our time line and the tech said there was only one baby. Is it possible they missed a baby? Has anyone else experienced this?