Hi Doctor, My Daughter Was 2 Yrs Old.she Passes His

Hi doctor,
My daughter was 2 yrs old.she passes his poo regularly.suddenly,she feels pain,hard stools,she has hand sucking nowadays more.not eating properly,not drinking.even as i forcing her to do,she crying and get vomited.while passing stool,she was crying.please help me to sort out the issue.please provide your valuable response immediately for tight motion,to quit hand sucking and to make her to increase the apetite.(she was not interested in eating ...?)