5 months pregnant

Hello everyone. This is my third pregnancy . And this pregnancy is the first time it happen to me . Basically doctor give me some anti medication and the previous pregnancy also have. BUT this time round i keep on vomitting , having diarrhea , fever and feeling so weak. My temp is 38.7 . And whatever i eat or drink i will vomit back . My tummy feel so empty. What shall i do now? Is been two days ald im like this.. :(