How are you? Rash or pimple on the shaft may be attributed to irritation, inflammation, skin infection or skin issues such as dermatitis. This does not necessarily be caused by a bladder infection. There may be an association with blood in the urine though especially if there is history of urinary stones. Management for bladder infections usually involves antibiotics. If the symptoms persist, it is best that you have this checked by your doctor for proper evaluation. Take care and do keep us posted.