What Causes Headache, Rash On Arm And High Fever?

ok my daughter had a headach,rash on her arm, she said her leggs hurt.she ran a high fever for about 4 days. it finaly broke, now i think i have it and my youngest daughter. what do i need to do? my youngest is coughing ,no other symptoms yet. my throat is hurting and swollen i have body aches and my head started pounding last night.