My child comes back from her dad's with cold like symptoms. i just found out she could have been exposed to meth. how will i know for sure?

Symptoms: You can get her tested but then if she does not show any sign of anxiety, hyperactivity, tremor, fast speech etc, why bother unless you want proof for a custody issue. You should be concerned over the safety of your child when in her father's care. Perhaps asking the court to get the dad tested for drug may be a better solution. You may check with your city's child care service re. options.