I started having the chills, fatigue, body aches, sore throat, and fever. the back of my neck has been hurting very bad. could i have mono?

Possibly: Since you are running a fever and are in general not feeling well. I recommend that you go to your family doctor or to a walk-in clinic. You should have your diagnosis confirmed. Having a stiff neck can be part of mono but it could also be part of something more serious and i think that you should definitely be checked out by a medical professional this morning.

See a doc: This does not sound like mono. It could be enterovirus, which is not pleasant but not dangerous, or it could be bacterial meningitis which is dangerous and life threatening. If i see a patient like this they go directly to the er.