Heavily Pregnant yet made to stand in a long queue

On the 24th October 2017 between 12: 35 - 12:49 a cashier working at till number 4, a So the queue at that time of the day are extremely long, me being pregnant I went straight to the till for obvious reasons ( I can't stand for too long), When I got to her , the till was empty as in she was not serving a customer, so she rudely asked me to go queue like the rest of the people because I'm not disabled as well as mentioned that customers will complain, there was no one complaining about me jumping the queue but her, so not wanting to cause a scene I went to queue like everyone else when I got to the front of the queue the lady that assisted me asked why I stood in the long queue in my condition. The sad part is its was not the first-time for me to get that woollies while pregnant other cashier assisted me without a fuss, I urge the management to train their stuff well and if need be put up a notice that Pregnant woman will not be given preferential treatment , you have a good brand you can't let your untrained stuff members ruin it for you. I'm so disappointed about that street-mate attitude I got from you cashier.