Hyperemesis starting at 14 weeks

Has anyone experienced hyperemesis/severe morning sickness that didnt start until the second trimester? I had bad morning sickness from 5 weeks but by 9-10 weeks it started to improve. I was almost feeling back to normal and then at 14 weeks I suddenly couldn't stop vomiting and ended up in hospital over the weekend. Everything I've read says that it starts early on and should improve by 14-16 weeks, so I'm wondering what to expect since it started so late. Will it take ages to resolve? Even with medication I am really struggling and can't face the thought of weeks and weeks more of feeling like this!