Back ache. Congestion. Sore throat. Nausea. chest and adominal pain. Gas.?

Three days ago I woke up with a sore throat at first. Then it progressed to back aches and I was congested the whole time alwaysblowing my nose. Everything I eat has been coming back up and the nauseas feeling won't go away. I have been having gas alot lately and the chest/ adominal pain has been all over my stomach. Its been so severe I have problems trying to walk up and down stairs.Any ideas what I have?