Sitting there waiting for anything to happen or be told about Loki's state, Riza watched Banner work in hopes there was something they could do to help the sick god. With him being a frost giant, this might be indeed different and hopefully nothing life threatening. Thor too watched, knowing that this was different but in Asgard, they were able to give Loki medicine that would help. Thor didnt know that was in the medicine or how it was made but their mother always had it whenever Loki became sick. 
When it seemed Loki came too, she perked up again to hear Loki's question. But Thor answered. "You fainted. You were surcomed to stress, sorrow and regret to the point you became ill. Dr. Banner is checking you over." he explained to his brother. 
Riza sat there silently with nothing to say for she didnt know what to say until Tony entered the room. She stood and walked over to her father. "Don't know yet. I'll be fine, Thor is most likely fine, but Uncle Bruce is doing a check over in hopes we can do something to help break his fever if it really is one." She told him is a low tone that wouldnt break Banner's concentration. Pepper had come back with a bowl of hot water and a dry cloth, setting it on the bedside table. 

Steve sat there with Clint still while the hawk was seemingly nervous. "I'll take a wild guess and say that you wish Loki never showed up."