Not sure if i am leakin or it is pee.

hi i am 27 week's and I know to stop a week bladder is to do exercise I have been doin the pelvic exercise, but still each time I cough, sneeze. I end up having to change my underpants and pants at least 4 time or more durin the day, I have smelt it and it dose not have much of a smell to it, I had a midwive's appointment and there was no infection or any thing wronge when she did the test.