Hi MissYa,
First and foremost I'm so sorry to hear about your loss

very devastating! You've come to the right place where the ladies are very compassionate, helpful and super friendly. You'll feel at home with all of our lovely ladies and hope the positivity lifts you back up some.
As far as your questions... you'll probably spot/bleed for weeks. How far along were you? You may start bleeding again to pass those clots before af shows... if you spike a fever dont hesitate to go to the ER. Watch signs of infection.
You may or may not ovulate before getting your first af, your body has to go to completely zero hcg before it will ovulate since you don't while pg. Then af will show, you don't always have to ovulate to get an af either.