Nausea

Has anyone else been experiencing terrible nausea? I had started around 8 weeks it continued until 11 weeks then it stopped and started again at 13 weeks. I’m 16 weeks today and still at it. My doctor prescribed me Zofran and it works BUT it causes me to be constipated and TERRIBLE LINGERING headaches. I’m at a lost. I feel like if i take it I’ll be constipated with a bad headache and no nausea, but if i don’t take it I’m throwing up and losing weight. Anyone else was prescribed medicine, if so what medicine and what are the side effects? Or even better, what did you do for your uncontrollable nausea?