Hyperemesis Gravidarum (HG)

Have any of you dealt with HG before! It's servers morning sickness that can cause hospitalization. I got diagnosed with it my my OB yesterday and was told if it gets worse by even a touch to go to the ER because I can become dehydrated. It has gotten a bit worse but I'm hold my off for a bit longer since I am at work and I'm off in 20 mins. I just wanna know if anyone's been through it and how bad it cam really get