Itchy raised white spot near wrist/red around it. Iced it. White spot gone/stayed red. Swollen. Not red today/hurts a lot. Itch gone. I see no puncture. Can't rest arm/hurts to use. What happened?

Spider bite. This sounds like a possible spider or some other insect bite. The lack of persistent redness is a good sign but ongoing pain and swelling can be due to a spider bite. You should have an examination of your arm as soon as possible in view of these symptoms.