Hello, My Boyfriend And I Were About To Have Sex

Hello, my boyfriend and I were about to have sex today when we both noticed a small area of bumps on his shaft. He was tested in December as well as myself for stds, he told me that he masturbated the other day without lube and it was really dry so he thinks that's what caused these bumps to appear. Can you tell me if this could be a possibility or should we both get checked again?