Has anyone else been off work for an extended period after surgery?

I (almost 59, F) had cataract/glaucoma surgery last Friday, 8/28. There was some confusion as to when I could return to work. An optometrist who is doing her fellowship in the practice did my follow up last Saturday and said I could return Tuesday 9/1 and that I was recovering well.

I have a desk job but when I called my boss on Monday to tell her, she said HR required a fitness for duty form. So I got that in. The surgeon signed in and said I could go back 10/1 with no restrictions.

I see him again 9/11 for another follow up and have the same surgery on left eye 9/23.

I am not sure why work required a fitness for duty form when I was only out 2 days, and why the optometrist told me I could go back sooner than the surgeon did. I still have a bit of light sensitivity and irritation in the eye and am taking eyedrops and resting.

I am wondering if anyone else had to be off work longer than they thought. Thankfully this is covered by FMLA and I am using paid leave. Thanks