Hii , Welcome To HCM & Thanks For Asking Your Query Here First Of All Congratulations !!!! on Being Pregnant I have gone through Your query and will try to provide information you need on it as You did not mention about your experience in last 12 weeks of pregnancy and as u said you are feeling these symptoms in just last two days Dry mouth is a common symptom during the first trimester, Pregnancy hormonal changes leading to reduced saliva flow, causing the mouth to become dry also due to nausea you are not able to drink sufficient water and that may be the reason of dehydration and dry mouth and due to insufficient food intake you may feel sick and fatigue as you are entering second trimester , your nausea will be not like in first Trimester nausea can be controlled by Medication like Doxylamine Succinate but i would advise you to have a visit to Your obs/Gyne to have a check up to rule out any other medical condition and when u start feeling good , take proper rest , have a good and balance diet and take your medicine time to time ... so have a visit to your obs/gyne for further checkup and treatment i hope it helps get well soon & Thanks Again