Hi Stephie, I'm so sorry to hear you are suffering right now. We've all been there and know how miserable it is!
I was also diagnosed at 11 w/JRA (I'm 35 now), I had psorisis issues then as well, but for some reason, the rheumy I had at the time never addressed it or treated it. I have been dx since with RA and psoriatic arthritis.
I have yet to be able to get relief from a major outbreak on my own - Remicade had come to my rescue a the last most severe one. The biologicals do wonders. I'm off Remicade now and may be starting Enbrel in Jan or Feb. I've been taking Plaquinil since April (though it stay not to take w/psorisis, my doc wants me on it) and it's been doing wonders for the joints, the psorisis is slightly worse than it used to typically be, but I know overall my case is really mild by comparision and for the most part (knock on wood) it has been ugly but tolerable. None of the standard NSAID have ever helped me, Plaquinil is one of 3 meds I've actually felt results from the other 2 being Remicade and Sulfasalazdine.
Good luck - until the doctor is available, I guess I would sugest a baking soda bath to soften the skin (help the itchies?), and use some OTC creams - I found Cetaphil Cream to help a little when it gets painful. I didn't get much help from using cortizone cream - but you might find it helpful to put on first then "seal" it with a lotion or cream. Also, I found avoiding certain food helps (milk really aggrivates psorisis for me - but I have a problem with dairy.)
Happy New Year. **