What Causes Itchy Lumps On The Back Along With Night Sweats?

Recently developed red bumps on back , I am itchy, it is worse at night,I also have had night sweats and wake up flush, sweat is primarily around neck and feel flush but no fever and do not feel ill. Closest image is flea bites, but seem to have no fleas or bed bugs. Never had these bumps and have recently moved to new York from Denver about three months ago, I have no known allergies, I have had a full battery of test to try to determine a source of occassional asthma that is usually stress related. I have been under a lot of stress recently. Any suggestions, only itchy not painful