Cramps & spotting at 12 weeks..

So today I woke up with some cramping & brown spotting. So I decided to go get checked out. The doctor said the baby is going good, heart beat is great. But she said I had a little tear on my uterus where the baby is... so she said that’s what is causing my cramps & little spotting.. so I’m wondering has anybody gone through anything like that. I am 12 weeks today!