What this come up on my arm pics

[youreapretender]

Just noticed it, I think my arm looks a little swollen too ? Don't have psoriasis or anything, have hand eczema but that's over my knuckles not anywhere near my arms

Heat rash? It doesn't look like a bite, because normally they swell in ovals (a circle elongated along the length of the vein). Meningitis rash is more pinprickley, although you should make sure the rash disappears when you press against it.

Potentially also a reaction to a virus, if you are feeling more generally under the weather.

It's completely disappeared now ? How weird ! I was cleaning the bathroom just before I noticed it, maybe it was the flash bathroom spray i was using but never had an issue with it before