Firstly congratulations :) it’s m quite common and usually goes away by the 1st trimester. Best is to speak to your doctor about your discomforts.As he can prescribe something for the nausea. Meanwhile you could also try these: eating smaller but more frequent meals brushing your teeth and using mouthwash several times a day chewing sugarless gum or sucking hard sweets taking frequent, small sips of water.
Are you able to speak with your Supervisor or HR? You can ask for a transfer of duties during this period or at least speak to them so they can understand your situation. I hope you will ge through this phase soon. Hang on!