Worst service ever, I came with my sister to dinne...

Worst service ever, I came with my sister to dinner, she ordered the buffet and I ordered a burger of the menu. THE BURGER MADE HERE IS AT THE LEVEL OF BURGER KING OR MCDONALD. The waitress took the order of my sister and she left and didnt ask me for my order, I had to run after her and tell her that I want to order a burger and fries. I AM A PERSON WITH HIGH PRESSURE. She looked at me with attitude and did not reply me yes. Very Unprofessional. Then my sister was eating the Buffet while I was hungry waiting for my burger. It took like 30 minutes just a burger. My sister went to grab more food from the buffet and I was having a bite of her dish. The waitress told my sister that she will charge us twice the buffet because she saw me eating from my sister dish. My sister replied her that I was eating because I was starving. That day I wanted to speak to the manager but my sister calmed me down. I AM A PERSON WITH HIGH PRESSURE. I literally never will come back to this restaurant again.