4 weeks pregnant baby don't like food!

Now I love my food! I'm not over weight I'm 5,9 and about 11 half stone but I do like to eat and never miss a meal but since I found out I was pregnant I can't eat every thing I used to love makes me physically sick.. I'm drinking constantly .. and my portion sizes are like baby small... any advice I know it's not good not to eat.. I'm sick every morning and so far the only thing I can eat is fruit veg and I'm living on toast fruit and homous dip lol x