I Am Currently 28 Weeks 5 Days With My Second

I am currently 28 weeks 5 days with my second pregnancy. My first I had high blood pressure and my daughter was delivered via C-section at 37 weeks 4 days. This time around, I have polyhydramnios (25.7cm) and we are repeating the glucose testing tomorrow. Last week, I had an ultrasound at the hospital and everything with baby looks great. He is measuring 3lbs 3oz which is large in the 77th percentile and his stomach is in the 97th percentile which is the reason for the repeat glucose test. For two days now, I have been having random heartburn that comes out of no where and induces vomiting. Is the new symptoms of heartburn/vomiting cause for concern? What should I know about all symptoms and pregnancy at this point?