Dolphin - I JUST went through this exactly myself (quit smoking and get sick - ear, then nose, then cough). It was so horrible. My dr suggested Mucinex - it didn't help one bit (in fact, I think it made it worse). I called back after taking the meds for about 6 days. The sinus infection had turned into a nasty case of bronchitis. I called the dr and she gave me the zpak. It took the full 5 days to get ANY relief, but I am breathing good now. Oxygen is AWESOME! Sometimes the low risk of some antibiotics is worth the great gain of good health and breathing!
I see your post was a while ago, but I hope you are feeling better now!
Hon, it sounds like you have a sinus or bronchial infection. It alone won't cause harm to the baby but if left untreated it will be miserable for you! I think you should tell your dr. that about the green mucus stuff because usually that does mean you have an infection and there are a few of the different class antibiotics you can take that are safe for the baby. One of them is Zithromiocin or commonly known as the Z-pak. I have taken it before during pregnancy. I know I hated to take anything but I felt so much better when I took it. It's only a 5 day medicine and it clears out of your system fast.
After having a mc its so hard to know what to do because you always will blame yourself if something happens but you have to trust that God is in control! :)