Help! tender uterus?

Taya
Ok so in labour, my placenta ruptured and was in about 8 different pieces, i could not deliver it by myself, my dr had to put his hand in to get it out. I have since then been on antibiotics (im 5weeks pp) dealing with infection in my uterus. The hospital has been useless in dealing with it so i went to see a specialist, i have an ultrasound tomorrow to see if i have any retaining placenta, if i do i will need to have a D&C to remove it. Now the specialist also told me my uterus is feeling way to tender for 5weeks pp what does this mean? Has anyone experienced anything similar?
Any replies would be greatly appreciated
Thank you !