Thanks for using the forum. I am happy to address your questions, and my answer will be based on the information you provided here. Please make sure you recognize that this forum is for educational purposes only, and it does not substitute for a formal office visit with a doctor.
Without the ability to examine and obtain a history, I can not tell you what the exact cause of the symptoms is. However I will try to provide you with some useful information.
Thalamic strokes, depending on location within the thalamic area, can result in the feeling in nausea. However, primary headaches are very common as well. These include migraines. Migraines are typically one-sided, pounding, with nausea and/or vomiting, and may have light or sound sensitivity. Additionally, morning headaches can be a secondary headache to sleep apnea.
Benign intracranial hypertension, also called pseudotumor cerebri, or idiopathic intracranial hypertension, is a disorder characterized clinically by headaches and vision loss, and sometimes tinnitus (ringing in the ear that is synchronous with the pulse). Dizziness may also be a symptom. The headache is usually global (all over the head) and pressure-like; the headache presentation can be variable. BIH predominantly occurs in people who are overweight, women, and those taken specific medications such as retin-A (the acne medication), vitamin A, and tetracycline antibiotics. It is a clinical diagnosis and requires a spinal tap (or lumbar puncture) to evaluate the pressure of the fluid surrounding the brain and spinal cord.
Without further information about your headache, it is difficult to provide you with adequate information. However, it is important for you to understand that if your headaches change in character, you should seek an evaluation such as from a neurologist. Additionally, seeking a neurologist for your daily headache may be of benefit for diagnosis and management.
Thank you for this opportunity to answer your questions, I hope you find the information I have provided useful, good luck.