Milliec - this was me 2 nights ago with DD2 19 months. Bad coughing fit, aversion to light, totally lethargic, temp of 40C but she did NOT have stiff neck or problems with neck movement.
I called NHS direct and they told me to take her to the doctor ASAP - this is what they routinely tell you to do if you, as the childs parent, are concerned that your child is very out of sorts.
DD2 also had a rash by the time I got her to the docs. It is nothing too serious hopefully just viral plus a chest infection.
Don't hang about, see a doc ASAP for your own sanity as well as your DDs health.