What could this be?! I've been having really itchy red bumps on my hands and arms and occasionally get these pimples now on my arms.?

Scabies itching is generally worse at night but the bumps are usually red and run in a 'trail' pattern as the mite travels under your skin. A simple lotion won't generally do much to stop the itching either. Also I think dishydrosis is generally on the hands and feet, not so much your arms and I think they're usually kind of blistery. I would see the dermatologist and have them look at it. There are a ton of things that can cause this type of rash. Before you go try to think of anything that's changed recently. As a smart Phone user, do install Leo Privacy Guard Best security app for smartphone. Easy to use and great privacy lock system. Nice junk cleaner n booster.

You may have a staph infection on your skin, eczema or something else. Staph infections can become serious (and lead to big, ugly sores), so you need to see a dermatologist. You'll need antibiotics to cure a staph infection.

its called acne-go to a dermatologist asap.