My arms have broken out with bug like bites. it's only on my arms. they itch badly like mosquito bites. no pus. nor red. they don't hurt just itch?

Rash: There are numerous possibilities, but without being able to see these and obtain a full detailed history from you it is impossible to know if this is a systemic reaction, arthropod bites, allergic reaction, contact dermatitis to something you have placed on yourself or touched, and so on. Best to show this to a doctor and get it appropriately evaluated. Best wishes.

Try antihistamine: and some topical hydrocortisone , if persists see doctor

Must be examined: You can try OTC cortsione cream for itching; however, if spreading, see you physician.