Hi Jcoll!
Welcome to our little community!! As LadyJade has said, testing for any of these infections leaves a lot to be desired! So saying that someone doesn't have one of these infections simply because their blood test came back negative really isn't very accurate, as that person could still very likely have that infection!
For example, Dr. James Schaller (Tick-borne disease specialist and researcher) has stated, "No blood smear will be positive for Babesia unless you have a profoundly massive number of infected red blood cells, which is rare. Therefore, no blood smear should be considered negative unless it has been examined for thirty minutes."
www.personalconsult.com/posts/babesia-checklist.html Most of the headaches are likely due to the tick-borne infections your daughter has, so treatment for the infections is the only way to not harm her and relieve the headache - along with lots of detoxing!!
If you haven't already, it would be helpful for you to start with reading through the thread at the top of the forum titled,
"New to Lyme?...Start here!!", as it is packed full of important information, symptom lists (as Lyme rarely occurs by itself), helpful links and pdf's, how to detox when one has these infections, and a list of questions that you can ask any doctor that you are seeking treatment from!