Prenatals making me sick!

I’m 14 weeks, up until last week I have taken all my prenatals daily. But for some reason this past week everytime i take a prenatal I end up throwing up about 5-10 minutes later. If I skip the prenatal for the day I’ll be fine. What should I do? Should I keep taking them or stop taking them or how should I do it? My doctor prescribed me different ones but those cost $200 WITH insurance and I don’t have that right now. I’m worried that not taking them is bad?? This is my first pregnancy so I’m not sure how crucial prenatals are but I know you should take them. I usually take them at night so I can sleep through it but now I can’t sleep