Zyrtec Headache and Nausea, Insomnia, Flu, Legs, Sleep

I got so sick with headache, nausea and bodyaches I had to go to dr's and get an IV for fluids, shot to stop headache and nausea. Was sick for 4 day. when you have bodyaches and nausea, you think flu. Not the case with Zyrtec. I also had terrible muscle aches in upper back down from neck. Insomnia, hyperactive legs and arms at night keeping me from sleeping. Some nights no sleep at all til about 5am. Some nights alittle sleep and thrashing all night, other nights just layed still but no sleep. Mood was off, was not interested in things I usually am. Everything I ate on some days just went right through me, was going to bathroom all the time. Have been off for 5 weeks and still have the symptoms just not as bad on some days and just as bad sometimes. How long will this last??????