Any suggestions?

I’m 16 weeks, have had nausea and sickness throughout my pregnancy pretty bad. I started taking unisom and vitamin b6 as suggested by my OB and it got significantly better until this week. I’ve started vomiting everything again, including water. I can’t keep my prenatals down. I’ve talked to my OB but she just keeps saying “it’s normal, it’ll go away eventually”. It really is taking everything out of me and I just don’t know what else to do.