Cough that won't stop!

For 3 days now I've been so sick, cough super hard nonstop. It's gotten to the point that every time I cough, it feels like my uterus is contracting. It's painful and uncomfortable. (Im 21 weeks) I'm worried I can hurt the baby since they are already worried about a chance of the placenta aging too soon. 😞 I'm waiting for my doctor to call me back since he's been closed over the weekend. Any advice until then?!