Can i be fired for my doctor putting me on a 2 and a half week leave of absense?

My doctor put me on a leave of absence at work for head trauma. He said i could go back to work in a week or 5 business days. After the week was up I went back to work and was overwhelmed by how much work was waiting for me. My boss starting giving me all these timetables to finish the work which was stressful and my head started hurt but I was okay and felt I could finish within the timetable. All of my boss starts giving me other assignments that were new to me and would have made finishing my previous obligations impossible. I started getting bad anxiety to the point where I had a panic attack. I went to my bosses boss and told her that my head was really hurting and that I couldn’t continue. I went back to the doctor and told him what happened so he put out of work another week. I felt a lot better and confident I was okay to work. When I retrofit the second time nobody in my department said a word to me. Nobody. My boss was really making it obvious that she was mad at me by her actions like staring, ignoring, very short answers like she was to busy to help me or I should know what to do by now. She then has a meeting with us where she is literally pointing out my absence and how I created everyone else to be behind. She also changed our daily tasks which looked okay. I leave that day at 4pm and was really trying to get home as fast as I could because I just felt horrible. The next day my anxiety was really bad and I was amazed I made it to work. The first thing I do is check my emails. I see that she changed our daily tasks to where my tasks doubled and everyone else’s tasks were decreased. She sent this email at 4:01pm the previous day. She waited for me to leave to send the email and new i would then be the last to see it. Everyone is happy to see their workload decrease and if I complain they will be impossible for me to work with. Still for 3 days less than 20 words were said to me by my coworkers and only because they had to ask me about other accounts. I was going to bring it up still but my boss avoided me like no one ever has before. It’s miserable at work when 3 weeks ago work was great. I was then asked to go to my bosses boss office where the HR Manager was waiting. They were saying to my performance was below expectations and my boss was upset that I didn’t communicate with her the previous day and tasks weren’t finished. I had to remind or tell them about my injury and that the stress was giving me anxiety and I was getting headaches which was due to an injury I was out 2 and a half weeks for. I also stated my workload was doubled and I was unaware that tasks weren’t complete because of the lack of communication but it was somehow all my fault. I started letting them know my rights stated by the EEOC and they then changed their tone and showed concern for me. They told me to go to the doctor and they would pay me for the rest of the day. What do I do? Can they fire me? I’ve never been written up and have 4 years of good reviews about my work.