Itchy lupus rash

I think I'm confident that I know what's going on, but I kinda just wanted to "confirm" my suspicions.

Last Saturday was my town's Fall Festival Parade, which was great, but I was sitting with my left arm in direct sun for about two hours or more.  Of course, I had neglected to put sunblock on before going to the parade (I know, stupid!)  When I got home, I noticed that my left arm, left side of my face and left side of my chest were all pink (not burned, just had a bit of color)  from the sun, but definitely more noticeable on my arm.  I didn't think anything about it - figured oh good, I got a little color today.  Anyway, by later that night, my face and chest were no longer pink, but my left arm had actually gotten darker and it looked like a rash was developing.  By morning, the rash was definitely there and ITCHY!!!   It's now Wednesday and the rash is still there, just as bad and just as itchy.

I'm pretty confident that what I'm dealing with is a lupus rash from sun exposure - the rash is ONLY on my left arm where it was exposed to teh direct sunlight - you can clearly see the line where my shirt sleeve was.  I was also researching lupus rashes online yesterday and found pictures of a rash that looks identical to the one I have - subacute cutaneous rash.  The rash also is NOT weeping or oozing like a poison ivy or oak rash would.

The only thing that really is keeping me from 100% believing that is what's going on is that, while I've gotten rashes before from sun exposure with my lupus, as well as the "butterfly rash" across my face - I've not had this exact type of rash before.

How many of you have experienced different types of rashes from what you "normally" get?  Is it common to get a certain type of rash one time and a different lupus rash another time?  I know other symptoms can differ from one flare to another, so I'm guessing it's posible with the rashes also.

Now on to treatment - what would you suggest as a treatment for the rash?  I'm trying not to scratch it, but it is soooo itchy!  I've been using a topical hydrocortisone cream, which helps for about an hour, but not much longer than that.

By the way - I did forget to mention that the past week or so I've also noticed quite a bit more pain and off and on sore throats, so it is VERY possible that I've been in the midst of a full-blown lupus flare and then being out in the sun brought on this other symptom.  I hadn't fully attributed those other symptoms to my lupus, as I have other chronic pain issues that I thougth might be causing the increased pain and the ragweed has been relatively bad around here, so that's what I attributed teh off and on sore throat to - allergies.  But now with the rash, I'm thinking more and more that the lupus has been flaring.  It's so difficult sometimes deciphering these things when you have several different medical conditions going on. -- Very frustrating at times!!

Anyway - while I'd like to avoid it if I can, do you think it would be advisable for me to contact my doctor and see about getting a short round of prednisone to get things under control - both if it is a full blown flare or if it is a simple lupus rash?  I've used prednisone in the past for flares and it usually works quite well for me.

Any advice you can give would be greatly appreciated.  Thank you.