Hello I have read through your question and want to tell you that your symptoms are not due to simvastatin as it is only a cholesterol lowering agent. I would suggest you to get an EKG done to to know if there is any cardiac cause to the irregular heartbeat. Also regarding pain during micturition you should get an USG whole abdomen done to rule out any kidney stones. Also get a urine test done to rule out any infection. I hope that answers your question. Please feel free to write if you have any further questions