Girls, is it normal that she's constantly yelling? Should I go back to…

Girls, is it normal that she's constantly yelling? Should I go back to the hospital? Her appetite has disappeared again, I don't know what it is and we're not giving her anything except formula and water ? We just got over that illness, everything was fine ? and now her appetite disappears again and she yells all the time like she's howling and being fussy ?? I think I'm the worst mother ??