I have these pimple like bumps that started on my butt and spread down my legs and are now appearing on my neck face and arms they itch and are sore and if iscratch the form scabs but never really heal it has now spread to my arms face and neck and leaves

See a dermatologist. To make an accurate diagnosis you should see a skin doctor, but this sounds like an allergic reaction, either to something you are taking by mouth, or a contact dermatitis. If you have recently changed your shampoo, lotions, perfume, other, bring this info along with your visit to dermatologist. Hope the itching stops.