Hi, I Had An IUD Removed 6 Days Ago, I

Hi, I had an IUD removed 6 days ago, I had spotting for the first day, which turned into bouts of heavy blood loss. I passed many large clots, which I assume was my body eliminating the build up of the uterus lining that would have occurred while the IUD was in place. Now, however I have become quite dizzy and at time feel like I am going to pass out. I have been to the Dr and my vitals are all stable, a blood test has been done and there is no indication of anything that would be causing the light headedness. I have been told that it may be cervical excitation from the removal causing vasovagal symptoms - what does this mean and how long will it last?