Signs of preclampsia

Hi ladies I am currently 16 weeks pregnant and have been getting really like really bad headaches up to the point of getting nauseous and throwing up. And lately it has been super constant even when I just wake up in the morning and it'll last like half a day or even more and it'll come back at night. I had told my ob/gyn about it but she said it was normal due to the headaches but at this point I think it's too much I thought it can be preclampsia but normally it's after 20 weeks but I mean the symptoms sure feel like it ! anyone out there who had these symptoms this early in the pregnancy and found out what it was or what can I do ?

Thank you ❤️