Hi there,
How are you doing? I'm sorry that I didn't see your post sooner, I just haven't been on the forum much the past few days. I take enbrel too, I think I've been on it almost 4 months now. I don't ever remember having a reaction like that at all to the shot, did you call your doc? I am surprised that you felt it so soon, I thought it took several hours for the meds to get into your system, but I think I would certainly call someone. Have you tried the enbrel hotline? They have a nurse on call all the time to answer questions and address your concerns.
Please take care and let us know how you're doing!