Psychosomatic Allergy?

Whelpling

So I have suspected strep throat, for which my doc has prescribed Penicillin. I should state here that I'm generally a very anxious/stressy person. I took the first pill, aware that reaction to Penicillin was possible (despite having had no reaction whatsoever at any of the multiple points in my younger life where I took Penicillin). Anyway, I immediately got this all-over body itch and had some red patches come up on my chest, arms, thighs. Within an hour every last hive was gone and no other allergy symptoms at all.

Is it possible that I 'made' this happen just by being concerned (unduly, given past successful penicillin use) about allergy?

The exact same thing happened - twice - when I had injections of depo provera.

I feel fine now, apart from the strep, if a little paranoid (because my throat is feeling a little obstructed - as it has for the last few days at least).

So... am I worrying myself into hives? I do have chronic urticaria anyway, though the intense, all-over burning itch that's happened in the circumstances described above feels quite different, if a lot shorter-lived!