Hello, I would be happy to help you.
First of all, it sounds like you miscarried completely based solely on the ultrasound
which showed nothing in the uterus
. While I might have expected more bleeding than you describe, this must have been the entire pregnancy
On the other hand, if someone gave me your story, and then described the onset of significant one-sided pain, I would HAVE to entertain the idea that things were not as they seemed. Pain that is so bad that you cannot sleep cannot be ignored. While unlikely, the idea of an ectopic pregnancy (a pregnancy in a tube) must be entertained.
You need to call you OB/GYN and run this by them or their on-call person. One way to sort this out is to check an hCG
level and compare it to prior values (if it was drawn). You also need an exam and likely a repeat ultrasound. It is possible to be wrong, so don't ignore this pain. Good luck!!