FMLA Indiana

So I am due at the end of February with baby number 2. Since early on in my pregnancy I’ve suffered from “morning sickness” nothing seemed to help, so I was permitted intermittent FMLA days to take off by my doctor and work. I recently changed shifts at work and now I have a different supervisor is who very aware of my restrictions and FMLA sick leave. Not even a month into being on this new shift I had to leave a couple hours into being at work due to my stomach being messed up. This supervisor when told I needed to leave, replied with “God D$&@“ “just stay home and take care of yourself”. I walked away from the supervisor and did not say a word, I clocked out and left. I called my husband hysterically crying because I had never had any issues with my work before. I went to the doctor three days later and spoke to them and they told me I could start maternity leave early and provided me with a note. I took it to my HR and left, she has called me numerous times and keeps trying to push and question my doctors note. I called my doctor and they told me to give my HR their fax number and they would handle any issues. I am terrified of telling HR about the issue with the supervisor because of how things run in the company and I’m in fear of retaliation for speaking up. I will have my baby in three weeks or less and I just don’t want to have issues with having to leave work again and having the supervisor go off. I just want to have my baby and return to work after I’ve healed so I do not have to run into this issue again with the supervisor being so hostile.