Advice please😕

I am 34 weeks. I had an ultrasound a week ago, doctor said she is in 35th percentile. Her waist was measuring small so she is under weight. They are having me come in for another ultrasound on the 28th to see if my placenta is even feeding my baby or is the cord is tied. I keep getting really weak like I'm going to pass out, but they just say to Drink Apple juice or eat. It's not helping I get really hot and I have bumps on my stomach that burn when I itch them. My stomach also burns in the shower. I know my baby doesn't respond to ice cream and sometimes goes 12 hours without kicking. What should i do I feel horrible :(