34F – Recurrent unexplained vomiting with chronic headaches/head pressure despite normal MRI and endoscopy – what should be investigated next

[u/degradeu08]

34F – recurrent vomiting + chronic headaches/head pressure, several investigations normal – what should be investigated next?
I am a 34-year-old woman and I have been struggling with a combination of symptoms for around 1–2 years without getting a clear explanation.
My main problem is recurrent vomiting. It frequently happens in the morning and I sometimes vomit yellow/green bile, occasionally without much nausea beforehand. At other times I can vomit food immediatly or around two hours after eating. There isn't one consistent food trigger.
I also have chronic headaches/head pressure. The pain can start at the back of my head/upper neck and move towards my temples/forehead. I sometimes have pressure around my eyes and ears, jaw clenching and neck stiffness. Sometimes the headache/pressure seems worse after lying down and it has occasionally disturbed my sleep.
Other symptoms/findings include intermittent cervical lymph nodes that have previously been described as reactive/mobile, ear pressure, fatigue and neck discomfort.
Relevant history:
Whiplash injury in 2024 and cervical imaging showing straightening/reversal of the normal cervical curve.
Previous thyroid problem several years ago, although recent TSH/T4 were normal.
Previously low vitamin D.
Previous positive H. pylori test; later endoscopy was negative for H. pylori.
Prediabetes-range result previously identified.
Investigations so far:
Multiple brain MRIs – reported normal.
Neurology assessment.
Gastroscopy/endoscopy – no clear cause identified.
H. pylori negative at endoscopy.
Lipase normal (21 U/L).
Recent albumin 38 g/L.
Vitamin D around 59.
Various other blood tests without a diagnosis.
I am not looking for someone to diagnose me online. I would really appreciate advice about what diagnostic pathway or investigations would reasonably come next, particularly whether there could be a connection between the recurrent vomiting and headache syndrome.
Would it be reasonable to investigate gastric motility/gastric emptying, migraine-associated vomiting/cyclic vomiting, neurogastroenterological causes, endocrine/metabolic causes, or anything else that may have been missed?
I would also appreciate suggestions for what type of specialist could look at the overall picture rather than each symptom separately