Hello and welcome to HCM, I understand from your history that you had scratch from rusted metal but no bleeding. Injury from metal has high risk of transmitting tetanus. Thus metal injuries should be followed by tetanus toxoid infection. The site should be thoroughly cleaned with water and soap. However, absence of blood rules out any deep injury. Trauma to the buttock could have caused muscular injury. The muscle injury could be responsible for the muscular pain. Muscle pain required hot fomentation and muscle relaxants. You can consult your primary healthcare provider for clinical assessment and thus further management. Thanks and take care Dr Shailja P Wahal