You always have tough ones for us to help you decipher. I'm not sure how to help you interpret your vision as I'm not understanding from you what you saw and how it felt to you. I will say that when I get visions that are the strongest, I do get physical side effects. However, they are normally good feeling side effects like tingling or chills or a real happy butterfly in my stomach feeling. I do sometimes get a headache after a day of taking in too much. And I do know some empaths who get migraines often. But I'm not quite sure how that relates to you. You may want to start making notes of your visions and how you feel with each one to see if you can find a pattern to help explain what is happening. After taking notes I finally figured out in the last year which of my visions are what will happen and which ones are visions of what could happen.
I would not know how to explain your co-worker getting hurt in the same area as your vision. For me, my visions have nothing to do with what room or location I am in. So I'm not sure how to explain that for you. We all work differently. But I think we humans, and particularly us empaths, need listen to our gut instincts more often. When ideas and "voice in your head" suggestions pop into our heads, I think we need to trust them. If your gut instinct is that you are being pointed toward your friend, then I would trust in that and pursue it.