Yes, I had four days of flu-like symptoms and low-grade fever. The reaction was strong enough that it kept me out of work, so my doctor ended up prescribing a short steroid taper to get me out of the rut. I should add the caveat that I have had every type of COVID vaccine that has been available in the US—including J&J—and I am always sick for 3-5 days after. I’ve talked to my doctor about this, and she’s suggested taking ibuprofen and Benadryl in advance of vaccinations. The one time I did so I think it may have helped a bit. It was just difficult to time the four suggested doses, and the Benadryl made it hard to work the day of the vaccination.