Hi Bonny,
Hmm? You don't happen to be allergic to it are you?
I hope it's just a coincidence that maybe you were getting sick/fighting something off/or in a flare...that you would feel so awful afterwards.
I know that many times after I had a shot...the few days after I wouldd suffer bad fatigue, and still hit bad flares.
Report it to your rheummy...but I would say, if you don't have a big rash all over your body or a fever...give the Enbrel a lot more time. As myslef & so many others will say...it can takes months.
Best of luck, hang in there.