What Causes Spreading Rash On Body And Nausea?

Hi! I have a rash that i found a couple nights ago. the rash is on my chest and upper stomach on my right side but has spread to the other side too.. it just isn't as concentrated on that side. its more spread out. the rash is smooth. it doesnt have any raised bumps.. but its basically tiny pin prick red dots everywhere. it looks like capillaries burst. there is no redness in the skin around it. it's not painful or itchy. i was nausous last night and dont seem to have much of an appetite. do u have any idea what it might be??