Pregnant and disappointed with the service I received

I am 24 weeks pregnant and I was told to get a sugar test done which requires you to fast and three test is done in a hourly manner. My gynecologist informed me that I can go home and come back after every hour .Today at the lab I was met by one of the nurses who was unwelcoming at the Mount Edgecombe rooms .she didn't explain how the test would be done and was not even interested in what she was doing she looked more annoyed that I was there at 7 .I did the first bloods and my husband also had his to do so we waited and than I did my second bloods and was told the times for the next one .So we decide to go home when I came back the nurse started talking to me like she was in charge and I was a dumb person for leaving .she than scolded me for leaving and saying I won't get proper results cause I left and was probably doing work .I did advise her I went home and relaxed and didn't know I must not leave as doctor informed me I could go and come back .she didn't allow me to explain myself so I said I won't be using the lab.Than she goes to the gynecologist rooms and starts complaining to about me to the nurse there who than inform me that the doctor was wrong . Which I understand but the fact that she was rude to me was not taken in consideration she even threatened to speak to my gynecologist Doctor nandla and tell her Manger. I did call the Neuberg head office and no feedback was given to me . I waited to speak to my gynecologist as well and the nurses just looked at me like I was wrong. No regard that a pregnant woman fasted and was yelled at .Very disappointed and unsatisfied that no one from Neuberg office called and the nurse seems to have more say than us patients .