FMLA Retaliation and being placed unfairly on PIP? I believe there plan is to replace me with a male coworker as well. Do I have any legal optons?

At the end of July during my mid-year review I was told I was being placed on a PIP, and they were doing the final review of it. At the time I asked why I being placed on a PIP. I was told because I needed to be more strategic and forward thinking. 3 weeks later I never get the PIP. At the end of August I had to take intermit FMLA for my son who is autistic and was struggling with depression and anxiety. During the few weeks I had to be home with my son full time, my boss asked me to do some work from home. I agreed and wanted to be cooperative. Then on the last week I was home I was told I could no longer work at home and that I would not longer have that option, even when I return to work. I was allowed to work two days a month from home and our policy allows for up to 4. I had my year end PM with a valued performance rating My boss did state that I was still going to be place on a PIP. I then asked why and he at first did not want to share that with me while I was on FMLA.