Brief Answer:
Need more information- age? Gender? Other Medical issues, Medications?

Detailed Answer:
Thank you for your question.

I do not know your gender, age, or other relevant medical information/history, however, if you have symptoms of headaches, nausea, and FREQUENT urination which are obviously UNUSUAL for you then, I would be primarily concerned about a possible URINARY TRACT INFECTION which could either be a bladder infection (cystitis) or KIDNEY infection (pyelonephritis). Generally, a pyelonephritis is accompanied by fevers, chills, and low back pain so since you really didn't those symptoms my guess is the more likely cause of your symptoms (if infectious) would be a CYSTITIS.
It's possible that a URINALYSIS can tell whether or not you have an infection of the bladder or kidneys and if so, a culture and sensitivity of the urine may better determine which antibiotic you should best be prescribed.

Of course, there could be other metabolic types of problems such as HYPERGLYCEMIA or a diabetic decompensation of HYPERGLYCEMIA which can be easily diagnosed both by urine testing as well as a fingertip stick or blood work that can demonstrate your glycemic index to see if hyperglycemia could be responsible for your symptoms.
Along those lines just about any type of metabolic problem involving the elevation of blood sugar as a consequence could also give you these symptoms so problems with the adrenal glands, thyroidopathy, or other hormonal problems could give you the symptoms you refer.

In addition, if you are a young female, could you be pregnant?

The bottom line is that putting these symptoms together will require more information and best if you could be examined by a doctor so a full history and evolution of the symptoms can be known along with appropriate blood and urine tests.

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This query has utilized a total of 42 minutes of professional time in research, review, and synthesis for the purpose of formulating a return statement.

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