The first trimester can be a challenging time, but the worst of the symptoms should disappear when the second trimester finally rolls around. In the meantime, your partner can baby you and help you get through the tough times.
It's hard to keep up with housework and shopping when you barely have enough energy to make it through the day, so welcome your partner's offers to handle those tasks -- or consider farming them out to friends, relatives or even a housekeeping service if you can afford one. This includes cleaning the litter boxes (or not, rather) if you have cats to avoid the potential for contracting toxoplasmosis.
Some pregnant women can barely set foot inside a kitchen, let alone cooking. If your partner can't cook, he or she could even just handle ordering take-out or enlist the help of a friend. Since it can be hard to keep food down, your partner could also ensure that there's a supply of foods that "stick" and ones that help with nausea, such as ginger tea.
Mood swings around nine weeks are very common; your partner shouldn't take them personally. Just listening to your fears and concerns and providing reassurance can be helpful.