trinity1913,
I don't have any suggestions regarding the headaches. But I do want to offer support to you regarding the 'anxiety' diagnosis from family members.
My son, who is now a healthy adult, probably had Mastocytic Enterocolitis (ME) as a child although at that time he was not given that specific diagnosis. School staff, friends (who were health professionals), family members (also health professionals) and the first pediatric GI we saw all brushed off his symptoms of bleeding, strange bowel patterns, poor appetite, weight loss, pain, nausea, and fatigue as 'anxiety'. Now I have another family member who has anxiety severe enough that they require medication and therapy to treat it, so I am not discounting anxiety as a serious medical problem. However, the treatment for anxiety that may cause some digestive upset and the treatment for IBD that may get worse when one is anxious are very different; therefore, it is important to know which one you are dealing with.
One day when my son woke up with swollen fingers and toes in addition to his other symptoms, I absolutely insisted that he be seen again by another pediatric GI. After just having me complete a detailed questionnaire, the new GI was fairly certain of my son's diagnosis. He had a protein-losing enteropathy that the doctor thought was caused by an allergic-type response in his intestines to inhaled environmental allergens such as pollen. With the correct treatment, he was symptom-free within a year. (Fortunately ME is an IBD that is often cured with medication, unlike Crohn's and UC.)
So trinity1913, trust your mummy gut. None of the doubters have ever apologized for not recognizing what was happening to my son, nor for not supporting me (in fact, I was accused of being overprotective, and overstating the seriousness of his symptoms); but my adult son has thanked me several times for persisting in my advocacy for him so that he could grow into the fine young man that he is today.
There are many here on the forum that have been in your shoes--many the energy of our support help you to continue to seek health for your child. Good luck.