Nausea at 15 weeks

I'm so sick these days and am forcing myself to eat whatever for the baby, but I can't help but feel nauseous constantly. I was fine most of my first trimester, started feeling sick at 11 weeks and some days I'm fine, but most days I can't smell food without wanting to puke. I used to be okay with fruit, and now even that is starting to be an aversion. I don't know what else to do :(