Your condition is called a stress incontinence. This happens when your urinary splincter is not strong enough to hold back the urine. This sometimes happens when you are on diuretics, antidepressants, sedatives, narcotics, or nonprescription cold or diet medicines.
Try going to the toilet every 3 hours whether you feel like or not, and remember to push it all out and empty your bladder completely while at it.
I do a bit of pelvic exercises and it helps. When you sit or lyedown then contract the muscles you would use to stop urinating. Press them and squeeze for 3 seconds and then relax for 3 seconds. Do this ten times. It helps control when you need it the most.