Call you baby Dr only they can tell you what is safe when you are pregnant always talk to them from now on. You don't want to hurt your tiny baby.
Unless you've already done so, speak with your ob/gyn as soon as you can. Flu-like symptoms aren't uncommon in some pregnancies, but chest pressure and not being able to keep fluids down should be looked at more closely.
Take care, get plenty of rest, and speak w/ your Dr. soon!