Terrible rash from fasting?

I am on day 18 of my water fast, and I've had terrible rashes all over my chest. They cover my collar and continue to spread to my neck and back, with strange lumps under the skin in various locations. They started around 3-4 days ago and the only way I am able to cope with it is with lots of rash cream and keeping an ice pack on hand at all times, since even the rash cream doesn't completely help.

I cannot seem to get much sleep without being awaken a few hours later by terrible itching sensations. If I scratch any of these tiny spots, a sheering pain is followed shortly after, and the itching just persists. I'm just wondering if anyone else has had this and how long did it last them? Did it last the remainder of the fast? I really don't want to have to cut my fast short, because this is becoming unbearable!